Q. When I attempt to use a WMI probe I get an access denied error, but I use an NT Services probe on the same target using the same credentials.

A. Here are some helpful links on troubleshooting WMI:

If you are still having trouble, please enable detailed logging for "Command-Line Probes & Notifiers" and reprobe several of the offending devices. Then send us the debug log so we can get an idea of the problems you are having.

 Obtaining a detailed debug log

The option you want to enable is "Command-Line Probes & Notifiers".