Index: /trunk/src/VBox/Runtime/r3/win/fileaio-win.cpp
===================================================================
--- /trunk/src/VBox/Runtime/r3/win/fileaio-win.cpp	(revision 37606)
+++ /trunk/src/VBox/Runtime/r3/win/fileaio-win.cpp	(revision 37607)
@@ -189,5 +189,5 @@
 
     pReqInt->enmTransferDirection  = enmTransferDirection;
-    pReqInt->hFile                 = RTFileToNative(hFile);
+    pReqInt->hFile                 = (HANDLE)RTFileToNative(hFile);
     pReqInt->Overlapped.Offset     = (DWORD)(off & 0xffffffff);
     pReqInt->Overlapped.OffsetHigh = (DWORD)(off >> 32);
@@ -318,5 +318,5 @@
     RTFILEAIOCTX_VALID_RETURN(pCtxInt);
 
-    HANDLE hTemp = CreateIoCompletionPort(RTFileToNative(hFile), pCtxInt->hIoCompletionPort, 0, 1);
+    HANDLE hTemp = CreateIoCompletionPort((HANDLE)RTFileToNative(hFile), pCtxInt->hIoCompletionPort, 0, 1);
     if (hTemp != pCtxInt->hIoCompletionPort)
         rc = RTErrConvertFromWin32(GetLastError());