There are many reasons why WU will not work correct with the SCCM Agent.
Various fixes:
1. Run Windows Update and let the update fix the machine
2. Stop the Update Agent Service, Delete the Software Distribution folder and restart the service.
Here is yet another way:
WUAHandler.log:
Unable to find or read WUA Managed server policy.
Unable to read existing WUA Group Policy object. Error = 0x80004005.
Failed to Add Update Source for WUAgent of type (2) and id ({GUID}). Error = 0x80004005.
UpdatesHandler.oog:
Updates scan completion received, result = 0x80004005.
Try this:
C:\Windows\System32\GroupPolicy\Machine
Rename the Registry.pol file
Then re-run the Software Updates Scan Cycle in the Configmgr Actions tab.
then watch the logs:
WUAHandler.log:
Waiting for 2 mins for Group Policy to notify of WUA policy change...
Added Update Source ({GUID}) of content type: 2
Async searching of updates using WUAgent started.