Hello John Skenyon
Thank you for posting question to Microsoft Q&A Forum.
According to this issue, may I know if you encountered any issues after trying to delete an update on Oct.17? Did it return any error messages, or it allowed you to go back to previous update, but nothing changed?
For critical programs, as you mentioned that the icon still existed but they did not work - did they return any error messages when you tried to open them? Please provide screenshots or examples of the 2-3 apps that no longer worked with error messages. As for now when I do not have detailed information from you, my suggestions would be that you could try to run these commands within Command Prompt:
DISM /Online /Cleanup-Image /RestoreHealth
sfc /scannow
(Do notice the space between forward dash (/) in the command)
If this does not fix the issue, you could try to create a new Windows profile by following this article: https://support.microsoft.com/en-us/windows/manage-user-accounts-in-windows-104dc19f-6430-4b49-6a2b… (Add a user account section).
After being in a new Windows profile, please check on the apps and icons to see they appear normally.
I need more information in order to provide possible accurate troubleshooting steps. Please let me know whenever you have an update.
While our initial response may not fully resolve the issue, we truly appreciate your cooperation as we work together toward identifying the most effective solution.
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