I have the exact same problem. [snip] Rolling back KB4601319 corrected the issue.
Unfortunately, I can see the KB4601319 in the update history, but not in the "uninstall Updates" list :(
So no chance to get that working for now. On my laptop, everything is fine, on the (under the) desktop just one user account is affected - the onlyone having admin privileges. Who else.
Thanks Microsoft for hopefully looking into thie very soon!