diff --git a/include/WinStd/Sec.h b/include/WinStd/Sec.h
index 2a9275d2..7a691f16 100644
--- a/include/WinStd/Sec.h
+++ b/include/WinStd/Sec.h
@@ -35,7 +35,7 @@ static BOOLEAN GetUserNameExA(_In_ EXTENDED_NAME_FORMAT NameFormat, _Inout_ std:
     if (::GetLastError() == ERROR_MORE_DATA) {
         // Allocate buffer on heap and retry.
         sName.resize(ulSize - 1);
-        if (::GetUserNameExA(NameFormat, &ulSize[0], &ulSize))
+        if (::GetUserNameExA(NameFormat, &sName[0], &ulSize))
             return TRUE;
     }
     return FALSE;