Index: src/ch/MainWnd.cpp
===================================================================
diff -u -N -rcdf6a22ddf857f56ce2e27e26d8cd6f0b8034b2e -re667429b5d9008da845b7bd146a2581c38551dfd
--- src/ch/MainWnd.cpp	(.../MainWnd.cpp)	(revision cdf6a22ddf857f56ce2e27e26d8cd6f0b8034b2e)
+++ src/ch/MainWnd.cpp	(.../MainWnd.cpp)	(revision e667429b5d9008da845b7bd146a2581c38551dfd)
@@ -2084,32 +2084,32 @@
 
 void CMainWnd::OnPopupRegisterdll() 
 {
-	DWORD dwErr;
-	if ((dwErr=RegisterShellExtDll(_T("chext.dll"), true)) == 0)
+	HRESULT hResult = RegisterShellExtDll(_T("chext.dll"), true);
+	if(SUCCEEDED(hResult))
 		MsgBox(IDS_REGISTEROK_STRING, MB_ICONINFORMATION | MB_OK);
 	else
 	{
 		TCHAR szStr[256], szText[768];
-		FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, dwErr, 0, szStr, 256, NULL);
+		FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, hResult, 0, szStr, 256, NULL);
 		while (szStr[_tcslen(szStr)-1] == _T('\n') || szStr[_tcslen(szStr)-1] == _T('\r') || szStr[_tcslen(szStr)-1] == _T('.'))
 			szStr[_tcslen(szStr)-1]=_T('\0');
-		_sntprintf(szText, 768, GetResManager()->LoadString(IDS_REGISTERERR_STRING), dwErr, szStr);
+		_sntprintf(szText, 768, GetResManager()->LoadString(IDS_REGISTERERR_STRING), hResult, szStr);
 		AfxMessageBox(szText, MB_ICONERROR | MB_OK);
 	}
 }
 
 void CMainWnd::OnPopupUnregisterdll() 
 {
-	DWORD dwErr;
-	if ((dwErr=RegisterShellExtDll(_T("chext.dll"), false)) == 0)
+	HRESULT hResult = RegisterShellExtDll(_T("chext.dll"), false);
+	if(SUCCEEDED(hResult))
 		MsgBox(IDS_UNREGISTEROK_STRING, MB_ICONINFORMATION | MB_OK);
 	else
 	{
 		TCHAR szStr[256], szText[768];
-		FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, dwErr, 0, szStr, 256, NULL);
+		FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, hResult, 0, szStr, 256, NULL);
 		while (szStr[_tcslen(szStr)-1] == _T('\n') || szStr[_tcslen(szStr)-1] == _T('\r') || szStr[_tcslen(szStr)-1] == _T('.'))
 			szStr[_tcslen(szStr)-1]=_T('\0');
-		_sntprintf(szText, 768, GetResManager()->LoadString(IDS_UNREGISTERERR_STRING), dwErr, szStr);
+		_sntprintf(szText, 768, GetResManager()->LoadString(IDS_UNREGISTERERR_STRING), hResult, szStr);
 		AfxMessageBox(szText, MB_ICONERROR | MB_OK);
 	}
 }
Index: src/ch/register.cpp
===================================================================
diff -u -N -r4c272b19c74694c428c943011f279ec064fbd894 -re667429b5d9008da845b7bd146a2581c38551dfd
--- src/ch/register.cpp	(.../register.cpp)	(revision 4c272b19c74694c428c943011f279ec064fbd894)
+++ src/ch/register.cpp	(.../register.cpp)	(revision e667429b5d9008da845b7bd146a2581c38551dfd)
@@ -25,37 +25,29 @@
 #define new DEBUG_NEW
 #endif
 
-DWORD RegisterShellExtDll(LPCTSTR lpszPath, bool bRegister)
+HRESULT RegisterShellExtDll(LPCTSTR lpszPath, bool bRegister)
 {
-	DWORD dwErr=0;
-	CoInitialize(NULL);
+	HRESULT hResult = CoInitialize(NULL);
+	if(FAILED(hResult))
+		return hResult;
 
-	HINSTANCE hMod=LoadLibrary(lpszPath);	// load the dll
-	if (hMod != NULL)
+	HRESULT (STDAPICALLTYPE *pfn)(void);
+	HINSTANCE hMod = LoadLibrary(lpszPath);	// load the dll
+	if(hMod == NULL)
+		hResult = HRESULT_FROM_WIN32(GetLastError());
+	if(SUCCEEDED(hResult) && !hMod)
+		hResult = E_FAIL;
+	if(SUCCEEDED(hResult))
 	{
-		HRESULT (STDAPICALLTYPE *pfn)(void);
-		
 		(FARPROC&)pfn = GetProcAddress(hMod, (bRegister ? "DllRegisterServer" : "DllUnregisterServer"));
-		if (pfn == NULL || (*pfn)() != S_OK)
-		{
-			dwErr=GetLastError();
-			CoFreeLibrary(hMod);
-			CoUninitialize();
-			return dwErr;
-		}
-		else
-		{
-			CoFreeLibrary(hMod);
-			
-			// shut down the COM Library.
-			CoUninitialize();
-			return 0;
-		}
+		if(pfn == NULL)
+			hResult = E_FAIL;
+		if(SUCCEEDED(hResult))
+			hResult = (*pfn)();
+
+		CoFreeLibrary(hMod);
 	}
-	else
-	{
-		dwErr=GetLastError();
-		CoUninitialize();
-		return dwErr;
-	}
+	CoUninitialize();
+
+	return hResult;
 }
Index: src/ch/register.h
===================================================================
diff -u -N -r3493e9fc470285b0a0b417d50be281467a071eb7 -re667429b5d9008da845b7bd146a2581c38551dfd
--- src/ch/register.h	(.../register.h)	(revision 3493e9fc470285b0a0b417d50be281467a071eb7)
+++ src/ch/register.h	(.../register.h)	(revision e667429b5d9008da845b7bd146a2581c38551dfd)
@@ -20,6 +20,6 @@
 #ifndef __REGISTER_H__
 #define __REGISTER_H__
 
-DWORD RegisterShellExtDll(LPCTSTR lpszPath, bool bRegister);
+HRESULT RegisterShellExtDll(LPCTSTR lpszPath, bool bRegister);
 
 #endif
\ No newline at end of file