We're seeing this issue as well. It started occurring late May early June.

We've done all the steps suggested.

It happens to all users.

We're on the Accounting Desktop 2021 R10 - the most current release

Permissions are correct on server

UAC is disabled

- the first time a user tries to open a company file it takes 10 minutes to open!

-use task manager to close QB, relaunch and we get QB has stopped working

-third time we launch a company file it opens right away.

I've spent 2 hours on the phone with QB support with 3 different technicians.

And no effective solutions have been offered.