Yep, another MS FAIL
I'm glad my laptop survived the experience without getting these issues
problematic KB4517389 cumulative update (excerpt)
the October 8 update (another name for KB4517389) has been breaking the Start menu and causing a critical error.
According to Microsoft’s support documentation, the company claims that the issue is not significantly impacting a large number of users. That won’t be much comfort to the people who
are experiencing the problem. However, Microsoft does say that it is investigating the reports of the broken Start menu, though it does appear like the company is stumped about why this issue is occurring.
It’s yet another round of bad news for Microsoft when it comes to faulty Windows 10 updates, and the company needs to get on top of this fast –
otherwise its reputation could be irreparably damaged.