Index: src/chext/DropMenuExt.cpp
===================================================================
diff -u -N -r3d1de44762647618faf9b5b3a87f89b293899d8d -rc33d4855ebf17772c28012a66c829a1f21d080f5
--- src/chext/DropMenuExt.cpp	(.../DropMenuExt.cpp)	(revision 3d1de44762647618faf9b5b3a87f89b293899d8d)
+++ src/chext/DropMenuExt.cpp	(.../DropMenuExt.cpp)	(revision c33d4855ebf17772c28012a66c829a1f21d080f5)
@@ -119,9 +119,7 @@
 	TShellMenuItemPtr spRootMenuItem = m_tShellExtMenuConfig.GetCommandRoot();
 	m_tContextMenuHandler.Init(spRootMenuItem, hMenu, idCmdFirst, indexMenu, m_tShellExtData, m_tShellExtMenuConfig.GetShowShortcutIcons(), bIntercept);
 
-	HRESULT hResult = MAKE_HRESULT(SEVERITY_SUCCESS, FACILITY_NULL, m_tContextMenuHandler.GetLastCommandID() - idCmdFirst + 1);
-	BOOST_LOG_HRESULT(rLogger, hResult) << L"";
-	return hResult;
+	return MAKE_HRESULT(SEVERITY_SUCCESS, FACILITY_NULL, m_tContextMenuHandler.GetLastCommandID() - idCmdFirst + 1);
 }
 
 STDMETHODIMP CDropMenuExt::InvokeCommand(LPCMINVOKECOMMANDINFO lpici)
Index: src/chext/HResultFormatter.cpp
===================================================================
diff -u -N -r3d1de44762647618faf9b5b3a87f89b293899d8d -rc33d4855ebf17772c28012a66c829a1f21d080f5
--- src/chext/HResultFormatter.cpp	(.../HResultFormatter.cpp)	(revision 3d1de44762647618faf9b5b3a87f89b293899d8d)
+++ src/chext/HResultFormatter.cpp	(.../HResultFormatter.cpp)	(revision c33d4855ebf17772c28012a66c829a1f21d080f5)
@@ -34,6 +34,10 @@
 	case S_FALSE:
 		wstr << L" (S_FALSE)";
 		break;
+	case E_FAIL:
+		wstr << L" (E_FAIL)";
+		break;
+
 	default:
 		{
 			chcore::TString strDesc = chcore::TWin32ErrorFormatter::FormatWin32ErrorCodeWithFallback(hResult, nullptr, false);
Index: src/chext/ShellExtControl.cpp
===================================================================
diff -u -N -r3d1de44762647618faf9b5b3a87f89b293899d8d -rc33d4855ebf17772c28012a66c829a1f21d080f5
--- src/chext/ShellExtControl.cpp	(.../ShellExtControl.cpp)	(revision 3d1de44762647618faf9b5b3a87f89b293899d8d)
+++ src/chext/ShellExtControl.cpp	(.../ShellExtControl.cpp)	(revision c33d4855ebf17772c28012a66c829a1f21d080f5)
@@ -53,9 +53,9 @@
 	DWORD dwLastError = ERROR_SUCCESS;
 
 	m_hMemory = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, sizeof(SHELLEXT_DATA), _T("CHShellExtControlData"));    // name of map object
+	dwLastError = GetLastError();	// NOTE: last error is needed also for success case (for already exists status)
 	if(!m_hMemory)
 	{
-		dwLastError = GetLastError();
 		BOOST_LOG_HRESULT(rLogger, dwLastError) << L"Cannot create file mapping.";
 		ReleaseMutex(m_hMutex);
 		CloseHandle(m_hMutex);
@@ -65,7 +65,9 @@
 	m_pShellExtData = (SHELLEXT_DATA*)MapViewOfFile(m_hMemory, FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, 0);
 	if(!m_pShellExtData)
 	{
-		BOOST_LOG_SEV(rLogger, error) << L"Cannot map view of file.";
+		DWORD dwError = GetLastError();		// NOTE: do not overwrite dwLastError, as the value is needed later
+
+		BOOST_LOG_HRESULT(rLogger, dwError) << L"Cannot map view of file.";
 		ReleaseMutex(m_hMutex);
 		CloseHandle(m_hMutex);
 		CloseHandle(m_hMemory);
@@ -75,7 +77,14 @@
 
 	if(dwLastError != ERROR_ALREADY_EXISTS)
 	{
-		BOOST_LOG_SEV(rLogger, debug) << L"Copy Handler is not running. Disabling shell extension.";
+		if(dwLastError == ERROR_SUCCESS)
+		{
+			BOOST_LOG_SEV(rLogger, debug) << L"Copy Handler is not running. Disabling shell extension.";
+		}
+		else
+		{
+			BOOST_LOG_HRESULT(rLogger, dwLastError) << L"Copy Handler is not running. Disabling shell extension.";
+		}
 		m_pShellExtData->m_lFlags = 0;
 		m_pShellExtData->m_lID = GetTickCount();
 	}