New
#61
I thought I should report how I have achieved a degree of functionality for the moment.
I had the Start Menu Critical error a few weeks after upgrading from 8.1. I did find that uninstalling and then reinstalling Dropbox and Norton 360 cured the critical error message, and that was about six weeks ago and I have had no further such messages.
However, the Start Menu was wrecked, there were few tiles showing on it and none of the important ones. So I followed the instruction I had seen here and on Ten Forums to set up an administrator account and use that to replace the start menu in the faulty account (it is in C:\Users\Account Name\AppData\Local\TileDataLayer
This partially succeeded in that I had a normal sized Start menu with all the tiles but, unfortunately, most of then were pale blue and did not work.
So I set up another User Account completely and this worked perfectly, but I did not have access to any of my files, settings or bookmarks from the original still faulty account Trying to transfer or share them did not work well).
However this week my PC updated itself with the latest version of 10 (which I think was 10586, dated 12 Nov!). So optimistically I deleted the TileDataLayer folder in the faulty account and, again, replaced it by a copy of the from the Admin account. That has, largely, been successful. All of the tiles in the start menu of the faulty account now work, so I can use Edge, Word, Mail etc. However, some of the tiles are still pale blue rather than dark blue (as they were in the Admin account start menu) and Task Bar is not quite right in that the search box and the Edge icon are not there. But basically everything works, so I am well pleased. For how long remains to be seen.
Whether this will help anyone else I have no idea and I agree with others that it is a disgrace that Microsoft has allowed this to continue for so long and all this DIY has been necessary.