Portable Device Enumerator Service causes system to freeze

Hi. I've got a Windows 7 64-bit machine that is freezing shortly after logon. Windows Explorer is still responsive, but nothing else will launch. For example, if I shut down, the system will start to shut down but will stop and wait because the process playing the shutdown sound is not responding. The processor and RAM load is still low. So it seems everything new is queued behind some process that won't complete.

The system is clean according to both Malwarebytes and Symantec Endpoint Protection.

By process of elimination, I have found this freeze happens only when Windows' Portable Device Enumerator Service is enabled.

Now I'm stumped. I'm not really sure what this service does; it appears to have to do with group policies and plug-and-play USB devices. Any recommendations for what to try next to get this working normally?

I would start by doing a SFC. There's a tutorial on this site on how to do it.

Next I would use the Tweaking.com program to reset services permissions and startup states to the default, and maybe file and registry permissions as well. Be sure to take a Restore Point before using Tweaking. And if it makes things worse (not common, but it happens), run through it again.

Before doing any work on the system I recommend having all your data backed up, and even a system image to revert to.

Thank you so much for being willing to help. Unfortunately the user opted to wipe the machine and start fresh rather than diagnose the problem.

You're welcome. Glad it worked out.