Problem: I normally patch WSUS server at the end. I ran a quarterly patch on WSUS server itself. Couple of hours after patching I found out that clients were not reporting to WSUS console. I have a GP to let the clients contact WSUS every hour.

On the windowsupdate.log on the client machines. The following warning was registered.
#Warning: Failed to find update with error code 8024008.
-Windows Update client failed to detect with error 0x80244008

WSUS server event viewer:

Event ID : 1310
Event Code : 3007
Event Message ; A compilation error has occurred.
Application Virtual Path  /ClientWebService
Error  BC31007: Unable to open module file ‘C:WindowsMicrosoftFramework64v4.0.3031aTemporary ASP.Net Files…………..

Scouring the web, not close but got some clue that there might be permission issues.

Solution : Granted Full Access Rights to C:WindowsTemp folder to the group IIS_IUSRS.

Lo and Behold, no new error 1310 reported in WSUS event viewer and clients started reporting to the WSUS console.

I am not sure whether the new .Net updates /patches changed something but the above solution worked.