Using classic Outlook for Windows in business environments
The issue is back on our accounts too.
We're in a loop. It works for several hours without any action by us. And while staying in the same network it stops again for several hours.
The new test account I created some days ago has absolutely not the issue.
So this looks more and more that the account itself is part of the problem. Maybe a special setting is there on the new account, but not on the ones that existed as the issue came up end of January.