BTW it's probably not svchost itself that's a problem - it's a relatively trivial service managing app, loading service DLL or EXE files.
I got AutoPlay working. You're right, it wasn't svchost.exe. I did try renaming that executable only to find Remote Procedure Call (RPC) services died. Apparently, Windows fails to replace it with a fresh version from a *.cab file. Perhaps it's not important enough for auto cab-file replacement.
The problem is most likely registry setting based, as a corrupt .exe or .dll file would very likely give much worse problems...
Right again. This problem started after I uninstalled WinAmp two years ago. I installed CCleaner today and it removed some obsolete CLSID registry entries (old Windows ActiveX controls for Windows Explorer). I then compressed the registry.
Now AutoPlay works. I can't understand why that would have made a difference (perhaps someone could explain) or why MS AutoFix didn't fix it, but I'm glad it's working again.
Well, back to my original problem (which I never mentioned). I can't get launchU3.exe to continue running on my U3 Smart flash drive. I thought it was because AutoPlay wasn't working (which could have been a factor), but launchU3 continues to quit. Well, this is a new
topic; let's not discuss it here.