WSUS Client Diagnostic Tool:
The WSUS Client Diagnostic Tool is designed to aid the WSUS administrator in troubleshooting client machines which may be failing to report back to the WSUS Server. The tool will do a few preliminary checks and test the communication between the WSUS Server and the client machine.
Make sure you run WSUS Client Diagnostic Tool on 32 bit system only, as it support 32-bit system only and do not work on 64-bit system, else you will get following error:
WSUS Client Diagnostics Tool GetFileVersion(szEngineDir,&susVersion) failed with hr=0x80070002
The SimpleAuth Web Service is not working.
Error: The SimpleAuth Web Service is not working.
Event ID: 12042
Source: Windows Server Update Services
If you are getting following above and event ID, your need to check IIS settings.
Open IIS Administration: Go to Sites > WSUS Administration > SimpleAuthWebService – On right side Action panel click on “Basic Settings”, it will pop “Edit Application” window –
Verify the authentication and path is accessible by Web service.