diff --git a/src/msw/app.cpp b/src/msw/app.cpp
index 507b9be08a..8b0b20c33e 100644
--- a/src/msw/app.cpp
+++ b/src/msw/app.cpp
@@ -233,7 +233,7 @@ bool wxGUIAppTraits::DoMessageFromThreadWait()
     return evtLoop->Dispatch();
 }
 
-DWORD wxGUIAppTraits::WaitForThread(WXHANDLE hThread, int flags)
+WXDWORD wxGUIAppTraits::WaitForThread(WXHANDLE hThread, int flags)
 {
     // We only ever dispatch messages from the main thread and, additionally,
     // even from the main thread we shouldn't wait for the message if we don't