Angelika, are you running WIN 10 1803 Update and then unable to do an update after running the Windows Repair Tool? If so, you are in the same boat I was in. I resolved the problem with by running a DISM repair of Windows 10:
Using DISM with the RestoreHearlh option
Use the DISM command with the /RestoreHealth switch to scan the Windows image for any corruption and to perform a repair automatically. Unlike the /ScanHealth switch, the /RestoreHealth switch can take up to 20 minutes to complete the process.
To run the command do the following:
1. Use the Windows key + X keyboard shortcut to open the Power User menu and select Command Prompt (Admin).
2. Type the following command and press Enter:
DISM /Online /Cleanup-Image /RestoreHealth
It takes 20 minutes, but it resolved the issue completely....
Additional Info - I now this issue with a third PC and DSM did not fix the issue...going to have to do a clean install...
AlphaStealthHWSW