Hi HARALDKJELL,
1. You may also try resetting windows update components:
https://support.microsoft.com/en-us/kb/971058
2. Please delete SoftwareDistribution folder in C:\Windows\SoftwareDistribution;
1) In cmd, enter net stop wuauserv;
2) delete SoftwareDistribution Folder;
3) In cmd, enter net start wuauserv;
3. Please run sfc/scannow on the client, check if there are corrupted system files;
4. If after doing that, check windows update log again.
Best Regards,
Anne
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