An error occurred while creating an Outlook profile. How to overcome zero length OST file?

Question

Outlook

Colleagues, greetings
There is the following problem:
there is Exchange 2019 Standard (on VMware) with the latest updates (CU9 installed a month ago), clients - Outlook 2019 on a WS 2019 terminal server.
A couple of days ago, clients, initially existing, started complaining about an error when starting Outlook "Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The operation failed...". In this case, the OST file has a size of 0 (zero) kb
I created a test account, but I couldn't create a new profile in Outlook with the error "Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The file C:\Users\...\.ost is not an Outlook data file (.ost)." In this case, the OST file has a size of 0 (zero) kb. Attempts to enable full caching did not help.
OWA, EWS, Autodiscover, etc. - everything works like clockwork. Extended Outlook logging is enabled, but uninformative...
Who faced? How to overcome null OST file?
PS I can provide additional information within reasonable limits

Answer 1

In general, the issue is currently resolved by restoring the VM to the moment before the installation of the April updates.
Now I will slowly deal with the damaged VM updates.
Thanks to all