QB220 Pro random crashes on client PCS

The issue of Quickbooks 2020 pro on a Windows environment, crashes randomly thought-out the user session.
Completely stripe hosting server 2019 of QB2020, including all registry files. Reinstall fresh copy on server.
No errors in server event viewer.
Used QBToolHUB & File doctor with same results.
However, the following error in event viewer on client pcs (Win 10 Pro).
An unexpected error has occured in "QuickBooks Desktop Pro 2020":
DB error -308 ErrorMessage:'Connection was terminated' from file:'src\dmsqlprefattribute.cpp' at line 151 from function:'DMPrefAttribute::IDBPrefAttribute::DBLoad'
An unexpected error has occured in "QuickBooks Desktop Pro 2020":
ExecuteQuery failed (DETAIL AVAILABLE), error id: -6019, sub id: 0, 'Succeeded', ''
An unexpected error has occured in "QuickBooks Desktop Pro 2020":
DQE execution failed. Could not retrieve COUNT(user name).
An unexpected error has occured in "QuickBooks Desktop Pro 2020":
DB error -101 ErrorMessage:'Not connected to a database' from file:'src\dmsqltransaction.cpp' at line 173 from function:'DBMgr::SADMTransaction::DBSQLCommit'
Any guidance would be appreciated.
Jimmy