Error message: Sync Failed: WSUS Server not configured

SCCM Software Update Point (SUP) failed to sync from it parent site. shows error messages as per below log files.

Log file Name: wsyncmgr.log

Log File Name: wsusctrl.log

Also the following error message shows in Server Manager if you select WSUS:

The WSUS administration console has encountered an unexpected error. This may be a transient error; try restarting the administration console. If this error persists,
Try removing the persisted preferences for the console by deleting the wsus file under %appdata%\Microsoft\MMC\.
System.NullReferenceException -- Object reference not set to an instance of an object.


Stack Trace:
at Microsoft.UpdateServices.UI.SnapIn.Scope.ServerSummaryScopeNode.ResetScopeNode()


Try Deleting the wsus file under %appdata%\Microsoft\MMC\ in user Profile.

and try launching WSUS console it will open this time and sync will be fine.