Seeing the same problem in my company. It seems to have started on Wednesday this week. I have about 40 users, some on Win10, some Win11, and some also on Windows Server 2016. Running Office 365. MSACCESS.EXE does not drop from Task Manager after closing the window. Users are all using personal copies of a FE that has not changed in months.
I have confirmed with multiple users that they have the FE file location in their Trusted Locations, along with C:\Program Files\Microsoft Office\root\Office16. This does not fix the problem.
This cascades to other errors because next day the user starts a new window for Access, then opens the same FE file, and now some tables are locked, files are in use, etc. and my users swear that the error messages are wrong. Once we close all the Access tasks and start over, everything works again.