There are several possible causes that would impact a client's ability to report to the WSUS server.
Since the client does appear in the WSUS group, we can presume that basic connectivity and infrastructure is operational.
So, the first question is whether the client is attempting a call to the ReportingWebService, and what is happening in response to that attempt. This information can be traced through the WindowsUpdate.log. You should see two log entries similar to these near the bottom of the logfile:
2011-04-01 11:06:19:724 1608 ce8 Report Uploading 3 events using cached cookie, reporting URL = http://tr-wsus/ReportingWebService/ReportingWebService.asmx
2011-04-01 11:06:19:740 1608 ce8 Report Reporter successfully uploaded 3 events.
If the WindowsUpdate.log does not show a call to the ReportingWebService, the next item to determine is whether this client is a Configuration Manager client. If it is, then ConfigMgr controls the reporting functionality of the clients, and that reporting option would need to be enabled in the ConfigMgr console.
I am running into a similar issue except that Windows 7 machines are receiving updates and getting installed but they aren't checking back into the server. If I run check for updates on a affected client, it initiates contact with the server and then checks in. Why would Windows 7 behave this way? I have verified all the registry keys are correct, GPO settings are correct, WindowsUpdate.log is correct. I don't have block inheritance on the GPO. I have a login script that even initiates a gpupdate /force on all machines. Please help me understand what I should do to correct this issue? I know on a couple machines whether it's Windows 7 32 or 64 bit and I attampt to run clientdiag.exe I get 0x80070005 on most and 0x80070002 on a couple others.
depShane, email that WindowsUpdate.log to my attention and I'll see what I can figure out.
The error messages from the Client Diagnostic Tool on x64 systems are expected -- it's a 32-bit only tool.
I would be interested in seeing the results from the Client Diagnostic Tool on an x86 system.
Since this thread was originally created, SolarWinds has released a new Diagnostic Tool for the WSUS Agent which does work on both x64 and x86 systems.
If you are having issues with a client communicating with a WSUS server properly, download and run this tool on the client system. If you need assistance with the tool or interpreting its results, please post in the Diagnostic Tool forum.