We started using SCCM WSUS for workstation patches, but I always saw half machines success with half machines waiting for updates. It was always the typical error 80072EE2.
on the logs from WSUS, you often see w3wp.67 SoapUtilities.CreateException ThrowException: actor = https://xxx.com:8531/SimpleAuthWebService/SimpleAuth.asmx, ID=0c187b74-32e8-431f-946f-387b3730c7ee, ErrorCode=InternalServerError,
and often you cannot open WSUS console..nor connecting to the database via \\.\pipe\MICROSOFT##WID\tsql\query
When I rebooted the SCCM server with WSUS service, then most of the machines can get updates again…
I found out the reason is just WID(Windows Internal Database) cannot handle too many clients well, after I migrate WID to SQL, everything is working without any error.
Here are a few useful links on how to change WSUS WID to SQL:
http://www.havardkristiansen.com/2016/04/migrating-wsus-susdb-from-windows.html