diff --git a/src/msw/registry.cpp b/src/msw/registry.cpp
index 3739175728..010ff1d301 100644
--- a/src/msw/registry.cpp
+++ b/src/msw/registry.cpp
@@ -897,7 +897,7 @@ bool wxRegKey::QueryValue(const wxChar *szValue,
     {
 
         // first get the type and size of the data
-        DWORD dwType, dwSize;
+        DWORD dwType=REG_NONE, dwSize=0;
         m_dwLastError = RegQueryValueEx((HKEY) m_hKey, WXSTRINGCAST szValue, RESERVED,
                                         &dwType, NULL, &dwSize);
         if ( m_dwLastError == ERROR_SUCCESS )