Problem only in Vista (.net): call unmanaged dll(Shell32.dll, function: SHEmptyRecycleBin) from thread

Answer 1

I don't know WHY that's happening, but have you tried other threading methods? Such as a BackgroundWorker component or ThreadPool.QueueUserWorkItem? Does the error still happen?

Answer 2

Could it be because threads you create execute in the default security context, not in the security context of the main thread?

See the doc on ExecutionContext for a hint. You can set the ExecutionContext on your thread and re-try.

Answer 3

Have you called CoInitialize from your thread?

What error code is it returning?

Answer 4

Shell functions work with STA threads only, and .NET threads are MTA by default. You can set the thread to use single-apartment threading:

th->SetApartmentState(ApartmentState::STA);
th->Start();