diff --git a/include/WinStd/Common.h b/include/WinStd/Common.h
index b8408051..e5575538 100644
--- a/include/WinStd/Common.h
+++ b/include/WinStd/Common.h
@@ -243,23 +243,6 @@ inline SIZE_T SIZETAdd(SIZE_T a, SIZE_T b)
 /// \addtogroup WinStdStrFormat
 /// @{
 
-///
-/// Formats string using `printf()`.
-///
-/// \param[out] str       Buffer to receive string
-/// \param[in ] capacity  Size of `str` in characters
-/// \param[in ] format    String template using `printf()` style
-/// \param[in ] arg       Arguments to `format`
-///
-/// \returns Number of characters in result.
-///
-#if _MSC_VER <= 1600
-static int vsnprintf(_Out_z_cap_(capacity) char *str, _In_ size_t capacity, _In_z_ _Printf_format_string_ const char *format, _In_ va_list arg)
-{
-    return _vsnprintf(str, capacity, format, arg);
-}
-#endif
-
 ///
 /// Formats string using `printf()`.
 ///
@@ -290,22 +273,27 @@ static int vsprintf(_Inout_ std::basic_string<_Elem, _Traits, _Ax> &str, _In_z_
     _Elem buf[WINSTD_STACK_BUFFER_BYTES/sizeof(_Elem)];
 
     // Try with stack buffer first.
-    int count = vsnprintf(buf, _countof(buf) - 1, format, arg);
-    if (count >= 0) {
+    int count = vsnprintf(buf, _countof(buf), format, arg);
+    if (0 <= count && count < _countof(buf)) {
         // Copy from stack.
-        str.assign(buf, count);
-    } else {
-        for (size_t capacity = 2*WINSTD_STACK_BUFFER_BYTES/sizeof(_Elem);; capacity *= 2) {
-            // Allocate on heap and retry.
-            auto buf_dyn = std::make_unique<_Elem[]>(capacity);
-            count = vsnprintf(buf_dyn.get(), capacity - 1, format, arg);
-            if (count >= 0) {
-                str.assign(buf_dyn.get(), count);
-                break;
-            }
+        str.append(buf, count);
+        return count;
+    }
+    if (count < 0) {
+        switch (errno) {
+        case 0:
+            count = vsnprintf(NULL, 0, format, arg);
+            assert(count >= 0);
+            break;
+        case EINVAL: throw std::invalid_argument("invalid vsnprintf arguments");
+        case EILSEQ: throw std::runtime_error("encoding error");
+        default: throw std::runtime_error("failed to format string");
         }
     }
-
+    size_t offset = str.size();
+    str.resize(offset + count);
+    if (vsnprintf(&str[offset], count + 1, format, arg) != count)
+        throw std::runtime_error("failed to format string");
     return count;
 }
 
@@ -346,9 +334,9 @@ static _Success_(return != 0) int WideCharToMultiByte(_In_ UINT CodePage, _In_ D
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::WideCharToMultiByte(CodePage, dwFlags, lpWideCharStr, cchWideChar, NULL, 0, lpDefaultChar, lpUsedDefaultChar);
-        std::unique_ptr<CHAR[]> szBuffer(new CHAR[cch]);
-        cch = ::WideCharToMultiByte(CodePage, dwFlags, lpWideCharStr, cchWideChar, szBuffer.get(), cch, lpDefaultChar, lpUsedDefaultChar);
-        sMultiByteStr.assign(szBuffer.get(), cchWideChar != -1 ? strnlen(szBuffer.get(), cch) : (size_t)cch - 1);
+        sMultiByteStr.resize(cch);
+        cch = ::WideCharToMultiByte(CodePage, dwFlags, lpWideCharStr, cchWideChar, &sMultiByteStr[0], cch, lpDefaultChar, lpUsedDefaultChar);
+        sMultiByteStr.resize(cchWideChar != -1 ? strnlen(&sMultiByteStr[0], cch) : (size_t)cch - 1);
     }
 
     return cch;
@@ -399,9 +387,8 @@ static _Success_(return != 0) int WideCharToMultiByte(_In_ UINT CodePage, _In_ D
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::WideCharToMultiByte(CodePage, dwFlags, sWideCharStr.c_str(), (int)sWideCharStr.length(), NULL, 0, lpDefaultChar, lpUsedDefaultChar);
-        std::unique_ptr<CHAR[]> szBuffer(new CHAR[cch]);
-        cch = ::WideCharToMultiByte(CodePage, dwFlags, sWideCharStr.c_str(), (int)sWideCharStr.length(), szBuffer.get(), cch, lpDefaultChar, lpUsedDefaultChar);
-        sMultiByteStr.assign(szBuffer.get(), cch);
+        sMultiByteStr.resize(cch);
+        cch = ::WideCharToMultiByte(CodePage, dwFlags, sWideCharStr.c_str(), (int)sWideCharStr.length(), &sMultiByteStr[0], cch, lpDefaultChar, lpUsedDefaultChar);
     }
 
     return cch;
@@ -428,10 +415,9 @@ static _Success_(return != 0) int SecureWideCharToMultiByte(_In_ UINT CodePage,
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::WideCharToMultiByte(CodePage, dwFlags, lpWideCharStr, cchWideChar, NULL, 0, lpDefaultChar, lpUsedDefaultChar);
-        std::unique_ptr<CHAR[]> szBuffer(new CHAR[cch]);
-        cch = ::WideCharToMultiByte(CodePage, dwFlags, lpWideCharStr, cchWideChar, szBuffer.get(), cch, lpDefaultChar, lpUsedDefaultChar);
-        sMultiByteStr.assign(szBuffer.get(), cchWideChar != -1 ? strnlen(szBuffer.get(), cch) : (size_t)cch - 1);
-        SecureZeroMemory(szBuffer.get(), sizeof(CHAR) * cch);
+        sMultiByteStr.resize(cch);
+        cch = ::WideCharToMultiByte(CodePage, dwFlags, lpWideCharStr, cchWideChar, &sMultiByteStr[0], cch, lpDefaultChar, lpUsedDefaultChar);
+        sMultiByteStr.resize(cchWideChar != -1 ? strnlen(&sMultiByteStr[0], cch) : (size_t)cch - 1);
     }
 
     SecureZeroMemory(szStackBuffer, sizeof(szStackBuffer));
@@ -490,10 +476,8 @@ static _Success_(return != 0) int SecureWideCharToMultiByte(_In_ UINT CodePage,
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::WideCharToMultiByte(CodePage, dwFlags, sWideCharStr.c_str(), (int)sWideCharStr.length(), NULL, 0, lpDefaultChar, lpUsedDefaultChar);
-        std::unique_ptr<CHAR[]> szBuffer(new CHAR[cch]);
-        cch = ::WideCharToMultiByte(CodePage, dwFlags, sWideCharStr.c_str(), (int)sWideCharStr.length(), szBuffer.get(), cch, lpDefaultChar, lpUsedDefaultChar);
-        sMultiByteStr.assign(szBuffer.get(), cch);
-        SecureZeroMemory(szBuffer.get(), sizeof(CHAR) * cch);
+        sMultiByteStr.resize(cch);
+        cch = ::WideCharToMultiByte(CodePage, dwFlags, sWideCharStr.c_str(), (int)sWideCharStr.length(), &sMultiByteStr[0], cch, lpDefaultChar, lpUsedDefaultChar);
     }
 
     SecureZeroMemory(szStackBuffer, sizeof(szStackBuffer));
@@ -520,9 +504,9 @@ static _Success_(return != 0) int MultiByteToWideChar(_In_ UINT CodePage, _In_ D
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::MultiByteToWideChar(CodePage, dwFlags, lpMultiByteStr, cbMultiByte, NULL, 0);
-        std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[cch]);
-        cch = ::MultiByteToWideChar(CodePage, dwFlags, lpMultiByteStr, cbMultiByte, szBuffer.get(), cch);
-        sWideCharStr.assign(szBuffer.get(), cbMultiByte != -1 ? wcsnlen(szBuffer.get(), cch) : (size_t)cch - 1);
+        sWideCharStr.resize(cch);
+        cch = ::MultiByteToWideChar(CodePage, dwFlags, lpMultiByteStr, cbMultiByte, &sWideCharStr[0], cch);
+        sWideCharStr.resize(cbMultiByte != -1 ? wcsnlen(&sWideCharStr[0], cch) : (size_t)cch - 1);
     }
 
     return cch;
@@ -573,9 +557,8 @@ static _Success_(return != 0) int MultiByteToWideChar(_In_ UINT CodePage, _In_ D
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::MultiByteToWideChar(CodePage, dwFlags, sMultiByteStr.c_str(), (int)sMultiByteStr.length(), NULL, 0);
-        std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[cch]);
-        cch = ::MultiByteToWideChar(CodePage, dwFlags, sMultiByteStr.c_str(), (int)sMultiByteStr.length(), szBuffer.get(), cch);
-        sWideCharStr.assign(szBuffer.get(), cch);
+        sWideCharStr.resize(cch);
+        cch = ::MultiByteToWideChar(CodePage, dwFlags, sMultiByteStr.c_str(), (int)sMultiByteStr.length(), &sWideCharStr[0], cch);
     }
 
     return cch;
@@ -602,10 +585,9 @@ static _Success_(return != 0) int SecureMultiByteToWideChar(_In_ UINT CodePage,
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::MultiByteToWideChar(CodePage, dwFlags, lpMultiByteStr, cbMultiByte, NULL, 0);
-        std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[cch]);
-        cch = ::MultiByteToWideChar(CodePage, dwFlags, lpMultiByteStr, cbMultiByte, szBuffer.get(), cch);
-        sWideCharStr.assign(szBuffer.get(), cbMultiByte != -1 ? wcsnlen(szBuffer.get(), cch) : (size_t)cch - 1);
-        SecureZeroMemory(szBuffer.get(), sizeof(WCHAR) * cch);
+        sWideCharStr.resize(cch);
+        cch = ::MultiByteToWideChar(CodePage, dwFlags, lpMultiByteStr, cbMultiByte, &sWideCharStr[0], cch);
+        sWideCharStr.resize(cbMultiByte != -1 ? wcsnlen(&sWideCharStr[0], cch) : (size_t)cch - 1);
     }
 
     SecureZeroMemory(szStackBuffer, sizeof(szStackBuffer));
@@ -664,10 +646,8 @@ static _Success_(return != 0) int SecureMultiByteToWideChar(_In_ UINT CodePage,
     else if (::GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Query the required output size. Allocate buffer. Then convert again.
         cch = ::MultiByteToWideChar(CodePage, dwFlags, sMultiByteStr.c_str(), (int)sMultiByteStr.length(), NULL, 0);
-        std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[cch]);
-        cch = ::MultiByteToWideChar(CodePage, dwFlags, sMultiByteStr.c_str(), (int)sMultiByteStr.length(), szBuffer.get(), cch);
-        sWideCharStr.assign(szBuffer.get(), cch);
-        SecureZeroMemory(szBuffer.get(), sizeof(WCHAR) * cch);
+        sWideCharStr.resize(cch);
+        cch = ::MultiByteToWideChar(CodePage, dwFlags, sMultiByteStr.c_str(), (int)sMultiByteStr.length(), &sWideCharStr[0], cch);
     }
 
     SecureZeroMemory(szStackBuffer, sizeof(szStackBuffer));
diff --git a/include/WinStd/Cred.h b/include/WinStd/Cred.h
index ab6b4355..4f778408 100644
--- a/include/WinStd/Cred.h
+++ b/include/WinStd/Cred.h
@@ -29,11 +29,9 @@ static BOOL CredProtectA(_In_ BOOL fAsSelf, _In_count_(cchCredentials) LPCSTR ps
         return TRUE;
     } else if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Allocate on heap and retry.
-        std::unique_ptr<char[]> buf(new char[dwSize]);
-        if (CredProtectA(fAsSelf, const_cast<LPSTR>(pszCredentials), cchCredentials, buf.get(), &dwSize, ProtectionType)) {
-            sProtectedCredentials.assign(buf.get(), dwSize - 1);
+        sProtectedCredentials.resize(dwSize - 1);
+        if (CredProtectA(fAsSelf, const_cast<LPSTR>(pszCredentials), cchCredentials, &sProtectedCredentials[0], &dwSize, ProtectionType))
             return TRUE;
-        }
     }
 
     return FALSE;
@@ -57,11 +55,9 @@ static BOOL CredProtectW(_In_ BOOL fAsSelf, _In_count_(cchCredentials) LPCWSTR p
         return TRUE;
     } else if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Allocate on heap and retry.
-        std::unique_ptr<wchar_t[]> buf(new wchar_t[dwSize]);
-        if (CredProtectW(fAsSelf, const_cast<LPWSTR>(pszCredentials), cchCredentials, buf.get(), &dwSize, ProtectionType)) {
-            sProtectedCredentials.assign(buf.get(), dwSize - 1);
+        sProtectedCredentials.resize(dwSize - 1);
+        if (CredProtectW(fAsSelf, const_cast<LPWSTR>(pszCredentials), cchCredentials, &sProtectedCredentials[0], &dwSize, ProtectionType))
             return TRUE;
-        }
     }
 
     return FALSE;
@@ -81,11 +77,9 @@ static BOOL CredUnprotectA(_In_ BOOL fAsSelf, _In_count_(cchCredentials) LPCSTR
         return TRUE;
     } else if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Allocate on heap and retry.
-        std::unique_ptr<char[]> buf(new char[dwSize]);
-        if (CredUnprotectA(fAsSelf, const_cast<LPSTR>(pszProtectedCredentials), cchCredentials, buf.get(), &dwSize)) {
-            sCredentials.assign(buf.get(), dwSize);
+        sCredentials.resize(dwSize - 1);
+        if (CredUnprotectA(fAsSelf, const_cast<LPSTR>(pszProtectedCredentials), cchCredentials, &sCredentials[0], &dwSize))
             return TRUE;
-        }
     }
 
     return FALSE;
@@ -109,11 +103,9 @@ static BOOL CredUnprotectW(_In_ BOOL fAsSelf, _In_count_(cchCredentials) LPCWSTR
         return TRUE;
     } else if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
         // Allocate on heap and retry.
-        std::unique_ptr<wchar_t[]> buf(new wchar_t[dwSize]);
-        if (CredUnprotectW(fAsSelf, const_cast<LPWSTR>(pszProtectedCredentials), cchCredentials, buf.get(), &dwSize)) {
-            sCredentials.assign(buf.get(), dwSize);
+        sCredentials.resize(dwSize - 1);
+        if (CredUnprotectW(fAsSelf, const_cast<LPWSTR>(pszProtectedCredentials), cchCredentials, &sCredentials[0], &dwSize))
             return TRUE;
-        }
     }
 
     return FALSE;
diff --git a/include/WinStd/Crypt.h b/include/WinStd/Crypt.h
index e8710f73..13e64c5f 100644
--- a/include/WinStd/Crypt.h
+++ b/include/WinStd/Crypt.h
@@ -26,10 +26,8 @@ static DWORD CertGetNameStringA(_In_ PCCERT_CONTEXT pCertContext, _In_ DWORD dwT
     DWORD dwSize = ::CertGetNameStringA(pCertContext, dwType, dwFlags, pvTypePara, NULL, 0);
 
     // Allocate buffer on heap to format the string data into and read it.
-    std::unique_ptr<char[]> szBuffer(new char[dwSize]);
-    dwSize = ::CertGetNameStringA(pCertContext, dwType, dwFlags, pvTypePara, szBuffer.get(), dwSize);
-    sNameString.assign(szBuffer.get(), dwSize - 1);
-    return dwSize;
+    sNameString.resize(dwSize - 1);
+    return ::CertGetNameStringA(pCertContext, dwType, dwFlags, pvTypePara, &sNameString[0], dwSize);
 }
 
 ///
@@ -44,10 +42,8 @@ static DWORD CertGetNameStringW(_In_ PCCERT_CONTEXT pCertContext, _In_ DWORD dwT
     DWORD dwSize = ::CertGetNameStringW(pCertContext, dwType, dwFlags, pvTypePara, NULL, 0);
 
     // Allocate buffer on heap to format the string data into and read it.
-    std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[dwSize]);
-    dwSize = ::CertGetNameStringW(pCertContext, dwType, dwFlags, pvTypePara, szBuffer.get(), dwSize);
-    sNameString.assign(szBuffer.get(), dwSize - 1);
-    return dwSize;
+    sNameString.resize(dwSize - 1);
+    return ::CertGetNameStringW(pCertContext, dwType, dwFlags, pvTypePara, &sNameString[0], dwSize);
 }
 
 ///
diff --git a/include/WinStd/MSI.h b/include/WinStd/MSI.h
index 31bcad3a..c2c46000 100644
--- a/include/WinStd/MSI.h
+++ b/include/WinStd/MSI.h
@@ -34,10 +34,8 @@ static UINT MsiGetPropertyA(_In_ MSIHANDLE hInstall, _In_z_ LPCSTR szName, _Inou
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to read the string data into and read it.
-        std::unique_ptr<char[]> szBuffer(new char[++dwSize]);
-        uiResult = ::MsiGetPropertyA(hInstall, szName, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiGetPropertyA(hInstall, szName, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -64,10 +62,8 @@ static UINT MsiGetPropertyW(_In_ MSIHANDLE hInstall, _In_z_ LPCWSTR szName, _Ino
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to read the string data into and read it.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[++dwSize]);
-        uiResult = ::MsiGetPropertyW(hInstall, szName, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiGetPropertyW(hInstall, szName, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -92,10 +88,8 @@ static UINT MsiRecordGetStringA(_In_ MSIHANDLE hRecord, _In_ unsigned int iField
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to read the string data into and read it.
-        std::unique_ptr<char[]> szBuffer(new char[++dwSize]);
-        uiResult = ::MsiRecordGetStringA(hRecord, iField, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiRecordGetStringA(hRecord, iField, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -122,10 +116,8 @@ static UINT MsiRecordGetStringW(_In_ MSIHANDLE hRecord, _In_ unsigned int iField
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to read the string data into and read it.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[++dwSize]);
-        uiResult = ::MsiRecordGetStringW(hRecord, iField, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiRecordGetStringW(hRecord, iField, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -150,10 +142,8 @@ static UINT MsiFormatRecordA(_In_opt_ MSIHANDLE hInstall, _In_ MSIHANDLE hRecord
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to format the string data into and read it.
-        std::unique_ptr<char[]> szBuffer(new char[++dwSize]);
-        uiResult = ::MsiFormatRecordA(hInstall, hRecord, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiFormatRecordA(hInstall, hRecord, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -180,10 +170,8 @@ static UINT MsiFormatRecordW(_In_opt_ MSIHANDLE hInstall, _In_ MSIHANDLE hRecord
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to format the string data into and read it.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[++dwSize]);
-        uiResult = ::MsiFormatRecordW(hInstall, hRecord, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiFormatRecordW(hInstall, hRecord, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -232,10 +220,8 @@ static UINT MsiGetTargetPathA(_In_ MSIHANDLE hInstall, _In_z_ LPCSTR szFolder, _
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to format the string data into and read it.
-        std::unique_ptr<char[]> szBuffer(new char[++dwSize]);
-        uiResult = ::MsiGetTargetPathA(hInstall, szFolder, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiGetTargetPathA(hInstall, szFolder, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -262,10 +248,8 @@ static UINT MsiGetTargetPathW(_In_ MSIHANDLE hInstall, _In_z_ LPCWSTR szFolder,
         return ERROR_SUCCESS;
     } else if (uiResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap to format the string data into and read it.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[++dwSize]);
-        uiResult = ::MsiGetTargetPathW(hInstall, szFolder, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), uiResult == ERROR_SUCCESS ? dwSize : 0);
-        return uiResult;
+        sValue.resize(dwSize++);
+        return ::MsiGetTargetPathW(hInstall, szFolder, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return uiResult;
@@ -288,10 +272,8 @@ static INSTALLSTATE MsiGetComponentPathA(_In_z_ LPCSTR szProduct, _In_z_ LPCSTR
         return state;
     } else if (state == INSTALLSTATE_MOREDATA) {
         // Allocate buffer on heap to format the string data into and read it.
-        std::unique_ptr<char[]> szBuffer(new char[++dwSize]);
-        state = ::MsiGetComponentPathA(szProduct, szComponent, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), state >= INSTALLSTATE_BROKEN ? dwSize : 0);
-        return state;
+        sValue.resize(dwSize++);
+        return ::MsiGetComponentPathA(szProduct, szComponent, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return state;
@@ -318,10 +300,8 @@ static INSTALLSTATE MsiGetComponentPathW(_In_z_ LPCWSTR szProduct, _In_z_ LPCWST
         return state;
     } else if (state == INSTALLSTATE_MOREDATA) {
         // Allocate buffer on heap to format the string data into and read it.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[++dwSize]);
-        state = ::MsiGetComponentPathW(szProduct, szComponent, szBuffer.get(), &dwSize);
-        sValue.assign(szBuffer.get(), state >= INSTALLSTATE_BROKEN ? dwSize : 0);
-        return state;
+        sValue.resize(dwSize++);
+        return ::MsiGetComponentPathW(szProduct, szComponent, &sValue[0], &dwSize);
     } else {
         // Return error code.
         return state;
diff --git a/include/WinStd/Sec.h b/include/WinStd/Sec.h
index 314d152e..96083633 100644
--- a/include/WinStd/Sec.h
+++ b/include/WinStd/Sec.h
@@ -34,11 +34,9 @@ static BOOLEAN GetUserNameExA(_In_ EXTENDED_NAME_FORMAT NameFormat, _Inout_ std:
     }
     if (::GetLastError() == ERROR_MORE_DATA) {
         // Allocate buffer on heap and retry.
-        std::unique_ptr<char[]> szBuffer(new char[ulSize]);
-        if (::GetUserNameExA(NameFormat, szBuffer.get(), &ulSize)) {
-            sName.assign(szBuffer.get(), ulSize);
+        sName.resize(ulSize - 1);
+        if (::GetUserNameExA(NameFormat, &ulSize[0], &ulSize))
             return TRUE;
-        }
     }
     return FALSE;
 }
@@ -64,11 +62,9 @@ static BOOLEAN GetUserNameExW(_In_ EXTENDED_NAME_FORMAT NameFormat, _Inout_ std:
     }
     if (::GetLastError() == ERROR_MORE_DATA) {
         // Allocate buffer on heap and retry.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[ulSize]);
-        if (::GetUserNameExW(NameFormat, szBuffer.get(), &ulSize)) {
-            sName.assign(szBuffer.get(), ulSize);
+        sName.resize(ulSize - 1);
+        if (::GetUserNameExW(NameFormat, &sName[0], &ulSize))
             return TRUE;
-        }
     }
     return FALSE;
 }
diff --git a/include/WinStd/WLAN.h b/include/WinStd/WLAN.h
index 8132a209..5d90b567 100644
--- a/include/WinStd/WLAN.h
+++ b/include/WinStd/WLAN.h
@@ -43,15 +43,15 @@ static DWORD WlanReasonCodeToString(_In_ DWORD dwReasonCode, _Inout_ std::basic_
         sSize = SIZETAdd(sSize, 1024);
         if (sSize > DWORD_MAX)
             throw std::runtime_exception("Data too big");
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[sSize]);
+        sValue.resize(sSize - 1);
 
         // Try!
-        DWORD dwResult = ::pfnWlanReasonCodeToString(dwReasonCode, static_cast<DWORD>(sSize), szBuffer.get(), pReserved);
+        DWORD dwResult = ::pfnWlanReasonCodeToString(dwReasonCode, static_cast<DWORD>(sSize), &sValue[0], pReserved);
         if (dwResult == ERROR_SUCCESS) {
-            SIZE_T sLength = wcsnlen(szBuffer.get(), sSize);
+            SIZE_T sLength = wcsnlen(&sValue[0], sSize);
             if (sLength < sSize - 1) {
                 // Buffer was long enough.
-                sValue.assign(szBuffer.get(), sLength);
+                sValue.resize(sLength);
                 return ERROR_SUCCESS;
             }
         } else {
diff --git a/include/WinStd/Win.h b/include/WinStd/Win.h
index 744ce99f..55aa983b 100644
--- a/include/WinStd/Win.h
+++ b/include/WinStd/Win.h
@@ -38,10 +38,10 @@ static DWORD GetModuleFileNameA(_In_opt_ HMODULE hModule, _Out_ std::basic_strin
     } else {
         for (DWORD dwCapacity = 2*WINSTD_STACK_BUFFER_BYTES/sizeof(char);; dwCapacity *= 2) {
             // Allocate on heap and retry.
-            std::unique_ptr<char[]> szBuffer(new char[dwCapacity]);
-            dwResult = ::GetModuleFileNameA(hModule, szBuffer.get(), dwCapacity);
+            sValue.resize(dwCapacity - 1);
+            dwResult = ::GetModuleFileNameA(hModule, &sValue[0], dwCapacity);
             if (dwResult < dwCapacity) {
-                sValue.assign(szBuffer.get(), dwResult);
+                sValue.resize(dwResult);
                 return dwResult;
             }
         }
@@ -67,10 +67,10 @@ static DWORD GetModuleFileNameW(_In_opt_ HMODULE hModule, _Out_ std::basic_strin
     } else {
         for (DWORD dwCapacity = 2*WINSTD_STACK_BUFFER_BYTES/sizeof(wchar_t);; dwCapacity *= 2) {
             // Allocate on heap and retry.
-            std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[dwCapacity]);
-            dwResult = ::GetModuleFileNameW(hModule, szBuffer.get(), dwCapacity);
+            sValue.resize(dwCapacity - 1);
+            dwResult = ::GetModuleFileNameW(hModule, &sValue[0], dwCapacity);
             if (dwResult < dwCapacity) {
-                sValue.assign(szBuffer.get(), dwResult);
+                sValue.resize(dwResult);
                 return dwResult;
             }
         }
@@ -88,18 +88,9 @@ static _Success_(return != 0) int GetWindowTextA(_In_ HWND hWnd, _Out_ std::basi
     // Query the final string length first.
     iResult = ::GetWindowTextLengthA(hWnd);
     if (iResult > 0) {
-        if (++iResult < WINSTD_STACK_BUFFER_BYTES/sizeof(char)) {
-            // Read string data to stack.
-            char szBuffer[WINSTD_STACK_BUFFER_BYTES/sizeof(char)];
-            iResult = ::GetWindowTextA(hWnd, szBuffer, _countof(szBuffer));
-            sValue.assign(szBuffer, iResult);
-        } else {
-            // Allocate buffer on heap and read the string data into it.
-            std::unique_ptr<char[]> szBuffer(new char[++iResult]);
-            iResult = ::GetWindowTextA(hWnd, szBuffer.get(), iResult);
-            sValue.assign(szBuffer.get(), iResult);
-        }
-        return iResult;
+        // Allocate buffer on heap and read the string data into it.
+        sValue.resize(iResult++);
+        return ::GetWindowTextA(hWnd, &sValue[0], iResult);
     }
 
     sValue.clear();
@@ -121,18 +112,9 @@ static _Success_(return != 0) int GetWindowTextW(_In_ HWND hWnd, _Out_ std::basi
     // Query the final string length first.
     iResult = ::GetWindowTextLengthW(hWnd);
     if (iResult > 0) {
-        if (++iResult < WINSTD_STACK_BUFFER_BYTES/sizeof(wchar_t)) {
-            // Read string data to stack.
-            wchar_t szBuffer[WINSTD_STACK_BUFFER_BYTES/sizeof(wchar_t)];
-            iResult = ::GetWindowTextW(hWnd, szBuffer, _countof(szBuffer));
-            sValue.assign(szBuffer, iResult);
-        } else {
-            // Allocate buffer on heap and read the string data into it.
-            std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[++iResult]);
-            iResult = ::GetWindowTextW(hWnd, szBuffer.get(), iResult);
-            sValue.assign(szBuffer.get(), iResult);
-        }
-        return iResult;
+        // Allocate buffer on heap and read the string data into it.
+        sValue.resize(iResult++);
+        return ::GetWindowTextW(hWnd, &sValue[0], iResult);
     }
 
     sValue.clear();
@@ -185,14 +167,14 @@ static _Success_(return != 0) DWORD ExpandEnvironmentStringsA(_In_z_ LPCSTR lpSr
         if (sSizeOut > DWORD_MAX)
             throw std::invalid_argument("String too big");
         DWORD dwSizeIn = static_cast<DWORD>(sSizeOut);
-        std::unique_ptr<char[]> szBuffer(new char[(size_t)dwSizeIn + 2]); // Note: ANSI version requires one extra char.
-        sSizeOut = ::ExpandEnvironmentStringsA(lpSrc, szBuffer.get(), dwSizeIn);
+        sValue.resize((size_t)dwSizeIn + 1); // Note: ANSI version requires one extra char.
+        sSizeOut = ::ExpandEnvironmentStringsA(lpSrc, &sValue[0], dwSizeIn);
         if (sSizeOut == 0) {
             // Error or zero-length input.
             break;
         } else if (sSizeOut <= dwSizeIn) {
             // The buffer was sufficient.
-            sValue.assign(szBuffer.get(), sSizeOut - 1);
+            sValue.resize(sSizeOut - 1);
             return static_cast<DWORD>(sSizeOut);
         }
     }
@@ -213,14 +195,14 @@ static _Success_(return != 0) DWORD ExpandEnvironmentStringsW(_In_z_ LPCWSTR lpS
         if (sSizeOut > DWORD_MAX)
             throw std::invalid_argument("String too big");
         DWORD dwSizeIn = static_cast<DWORD>(sSizeOut);
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[(size_t)dwSizeIn + 1]);
-        sSizeOut = ::ExpandEnvironmentStringsW(lpSrc, szBuffer.get(), dwSizeIn);
+        sValue.resize(dwSizeIn);
+        sSizeOut = ::ExpandEnvironmentStringsW(lpSrc, &sValue[0], dwSizeIn);
         if (sSizeOut == 0) {
             // Error or zero-length input.
             break;
         } else if (sSizeOut <= dwSizeIn) {
             // The buffer was sufficient.
-            sValue.assign(szBuffer.get(), sSizeOut - 1);
+            sValue.resize(sSizeOut - 1);
             return static_cast<DWORD>(sSizeOut);
         }
     }
@@ -455,15 +437,17 @@ static LSTATUS RegQueryStringValue(_In_ HKEY hReg, _In_z_ LPCSTR pszName, _Out_
     } else if (lResult == ERROR_MORE_DATA) {
         if (dwType == REG_SZ || dwType == REG_MULTI_SZ) {
             // The value is REG_SZ or REG_MULTI_SZ. Read it now.
-            std::unique_ptr<CHAR[]> szBuffer(new CHAR[dwSize / sizeof(CHAR)]);
-            if ((lResult = ::RegQueryValueExA(hReg, pszName, NULL, NULL, reinterpret_cast<LPBYTE>(szBuffer.get()), &dwSize)) == ERROR_SUCCESS) {
+            sValue.resize(dwSize / sizeof(CHAR) - 1);
+            if ((lResult = ::RegQueryValueExA(hReg, pszName, NULL, NULL, reinterpret_cast<LPBYTE>(&sValue[0]), &dwSize)) == ERROR_SUCCESS) {
                 dwSize /= sizeof(CHAR);
-                sValue.assign(szBuffer.get(), dwSize && szBuffer[dwSize - 1] == 0 ? dwSize - 1 : dwSize);
+                sValue.resize(dwSize && sValue[dwSize - 1] == 0 ? dwSize - 1 : dwSize);
             }
         } else if (dwType == REG_EXPAND_SZ) {
             // The value is REG_EXPAND_SZ. Read it and expand environment variables.
-            std::unique_ptr<CHAR[]> szBuffer(new CHAR[dwSize / sizeof(CHAR)]);
+            std::unique_ptr<CHAR[]> szBuffer(new CHAR[dwSize / sizeof(CHAR) + 1]);
             if ((lResult = ::RegQueryValueExA(hReg, pszName, NULL, NULL, reinterpret_cast<LPBYTE>(szBuffer.get()), &dwSize)) == ERROR_SUCCESS) {
+                dwSize /= sizeof(CHAR);
+                szBuffer[dwSize] = 0;
                 if (::ExpandEnvironmentStringsA(szBuffer.get(), sValue) == 0)
                     lResult = ::GetLastError();
             }
@@ -519,15 +503,17 @@ static LSTATUS RegQueryStringValue(_In_ HKEY hReg, _In_z_ LPCWSTR pszName, _Out_
     } else if (lResult == ERROR_MORE_DATA) {
         if (dwType == REG_SZ || dwType == REG_MULTI_SZ) {
             // The value is REG_SZ or REG_MULTI_SZ. Read it now.
-            std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[dwSize / sizeof(WCHAR)]);
-            if ((lResult = ::RegQueryValueExW(hReg, pszName, NULL, NULL, reinterpret_cast<LPBYTE>(szBuffer.get()), &dwSize)) == ERROR_SUCCESS) {
+            sValue.resize(dwSize / sizeof(WCHAR) - 1);
+            if ((lResult = ::RegQueryValueExW(hReg, pszName, NULL, NULL, reinterpret_cast<LPBYTE>(&sValue[0]), &dwSize)) == ERROR_SUCCESS) {
                 dwSize /= sizeof(WCHAR);
-                sValue.assign(szBuffer.get(), dwSize && szBuffer[dwSize - 1] == 0 ? dwSize - 1 : dwSize);
+                sValue.resize(dwSize && sValue[dwSize - 1] == 0 ? dwSize - 1 : dwSize);
             }
         } else if (dwType == REG_EXPAND_SZ) {
             // The value is REG_EXPAND_SZ. Read it and expand environment variables.
-            std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[dwSize / sizeof(WCHAR)]);
+            std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[dwSize / sizeof(WCHAR) + 1]);
             if ((lResult = ::RegQueryValueExW(hReg, pszName, NULL, NULL, reinterpret_cast<LPBYTE>(szBuffer.get()), &dwSize)) == ERROR_SUCCESS) {
+                dwSize /= sizeof(WCHAR);
+                szBuffer[dwSize] = 0;
                 if (::ExpandEnvironmentStringsW(szBuffer.get(), sValue) == 0)
                     lResult = ::GetLastError();
             }
@@ -623,8 +609,8 @@ static LSTATUS RegLoadMUIStringW(_In_ HKEY hKey, _In_opt_z_ LPCWSTR pszValue, _O
         sOut.assign(szStackBuffer, wcsnlen(szStackBuffer, dwSize/sizeof(wchar_t)));
     } else if (lResult == ERROR_MORE_DATA) {
         // Allocate buffer on heap and retry.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[(dwSize + sizeof(wchar_t) - 1)/sizeof(wchar_t)]);
-        sOut.assign(szBuffer.get(), (lResult = RegLoadMUIStringW(hKey, pszValue, szBuffer.get(), dwSize, &dwSize, Flags, pszDirectory)) == ERROR_SUCCESS ? wcsnlen(szBuffer.get(), dwSize/sizeof(wchar_t)) : 0);
+        sOut.resize((dwSize + sizeof(wchar_t) - 1)/sizeof(wchar_t) - 1);
+        sOut.resize((lResult = RegLoadMUIStringW(hKey, pszValue, &sOut[0], dwSize, &dwSize, Flags, pszDirectory)) == ERROR_SUCCESS ? wcsnlen(&sOut[0], dwSize/sizeof(wchar_t)) : 0);
     }
 
     return lResult;
@@ -653,10 +639,10 @@ static _Success_(return > 0) int NormalizeString(_In_ NORM_FORM NormForm, _In_ L
                 for (int i = 10; i--;) {
                     // Allocate buffer. Then convert again.
                     cch = -cch;
-                    std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[cch]);
-                    cch = ::NormalizeString(NormForm, lpSrcString, cwSrcLength, szBuffer.get(), cch);
+                    sDstString.resize((size_t)cch - 1);
+                    cch = ::NormalizeString(NormForm, lpSrcString, cwSrcLength, &sDstString[0], cch);
                     if (cch > 0) {
-                        sDstString.assign(szBuffer.get(), cwSrcLength != -1 ? wcsnlen(szStackBuffer, cch) : (size_t)cch - 1);
+                        sDstString.resize(cwSrcLength != -1 ? wcsnlen(&sDstString[0], cch) : (size_t)cch - 1);
                         break;
                     }
                     if (::GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
@@ -696,12 +682,10 @@ static _Success_(return > 0) int NormalizeString(_In_ NORM_FORM NormForm, _In_ c
                 for (int i = 10; i--;) {
                     // Allocate buffer. Then convert again.
                     cch = -cch;
-                    std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[cch]);
-                    cch = ::NormalizeString(NormForm, sSrcString.c_str(), (int)sSrcString.length(), szBuffer.get(), cch);
-                    if (cch > 0) {
-                        sDstString.assign(szBuffer.get(), cch);
+                    sDstString.resize(cch - 1);
+                    cch = ::NormalizeString(NormForm, sSrcString.c_str(), (int)sSrcString.length(), &sDstString[0], cch);
+                    if (cch > 0)
                         break;
-                    }
                     if (::GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
                         sDstString.clear();
                         break;
@@ -807,10 +791,8 @@ static _Success_(return != 0) int GetDateFormatA(_In_ LCID Locale, _In_ DWORD dw
     int iResult = GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, NULL, 0);
     if (iResult) {
         // Allocate buffer on heap and retry.
-        std::unique_ptr<char[]> szBuffer(new char[iResult]);
-        iResult = GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, szBuffer.get(), iResult);
-        sDate.assign(szBuffer.get(), iResult ? iResult - 1 : 0);
-        return iResult;
+        sDate.resize(iResult - 1);
+        return GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, &sDate[0], iResult);
     }
 
     return iResult;
@@ -827,10 +809,8 @@ static _Success_(return != 0) int GetDateFormatW(_In_ LCID Locale, _In_ DWORD dw
     int iResult = GetDateFormatW(Locale, dwFlags, lpDate, lpFormat, NULL, 0);
     if (iResult) {
         // Allocate buffer on heap and retry.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[iResult]);
-        iResult = GetDateFormatW(Locale, dwFlags, lpDate, lpFormat, szBuffer.get(), iResult);
-        sDate.assign(szBuffer.get(), iResult ? iResult - 1 : 0);
-        return iResult;
+        sDate.resize(iResult - 1);
+        return GetDateFormatW(Locale, dwFlags, lpDate, lpFormat, &sDate[0], iResult);
     }
 
     return iResult;
@@ -976,10 +956,10 @@ static _Success_(return != 0) BOOL QueryFullProcessImageNameA(_In_ HANDLE hProce
     }
     for (DWORD dwCapacity = 2 * WINSTD_STACK_BUFFER_BYTES / sizeof(char); GetLastError() == ERROR_INSUFFICIENT_BUFFER; dwCapacity *= 2) {
         // Allocate on heap and retry.
-        std::unique_ptr<char[]> szBuffer(new char[dwCapacity]);
+        sExeName.resize(dwCapacity - 1);
         dwSize = dwCapacity;
-        if (::QueryFullProcessImageNameA(hProcess, dwFlags, szBuffer.get(), &dwSize)) {
-            sExeName.assign(szBuffer.get(), dwSize);
+        if (::QueryFullProcessImageNameA(hProcess, dwFlags, &sExeName[0], &dwSize)) {
+            sExeName.resize(dwSize);
             return TRUE;
         }
     }
@@ -1005,10 +985,10 @@ static _Success_(return != 0) BOOL QueryFullProcessImageNameW(_In_ HANDLE hProce
     }
     for (DWORD dwCapacity = 2 * WINSTD_STACK_BUFFER_BYTES / sizeof(wchar_t); GetLastError() == ERROR_INSUFFICIENT_BUFFER; dwCapacity *= 2) {
         // Allocate on heap and retry.
-        std::unique_ptr<wchar_t[]> szBuffer(new wchar_t[dwCapacity]);
+        sExeName.resize(dwCapacity - 1);
         dwSize = dwCapacity;
-        if (::QueryFullProcessImageNameW(hProcess, dwFlags, szBuffer.get(), &dwSize)) {
-            sExeName.assign(szBuffer.get(), dwSize);
+        if (::QueryFullProcessImageNameW(hProcess, dwFlags, &sExeName[0], &dwSize)) {
+            sExeName.resize(dwSize);
             return TRUE;
         }
     }
@@ -2145,11 +2125,9 @@ _Success_(return != 0) BOOL GetThreadPreferredUILanguages(_In_ DWORD dwFlags, _O
         ulSize = 0;
         GetThreadPreferredUILanguages(dwFlags, pulNumLanguages, NULL, &ulSize);
         // Allocate on heap and retry.
-        std::unique_ptr<WCHAR[]> szBuffer(new WCHAR[ulSize]);
-        if (GetThreadPreferredUILanguages(dwFlags, pulNumLanguages, szBuffer.get(), &ulSize)) {
-            sValue.assign(szBuffer.get(), ulSize - 1);
+        sValue.resize(ulSize - 1);
+        if (GetThreadPreferredUILanguages(dwFlags, pulNumLanguages, &sValue[0], &ulSize))
             return TRUE;
-        }
     }
     return FALSE;
 }