made sure the time and date is correct on the computer ?
Is your anti virus program up to date ?
Maybe disable the anti virus and give it a try
Medion MS-7713 AMD Radeon HD 6450 4.00 GB RAM
64-bit operating system processor cores 4
Windows 7 Updated to SP1 . Last successful update was windows update of update system but now simply not finding any further updates over several fruitless days.
Tried WindowsUpdateDiagnostic.diagcab which says
"Problems installing recent updates" - not fixed.
"Service Registration is missing or corrupt" - fixed