@ott I’ve experienced similar but on Outlook 2010, where deleting or moving lots of emails at once would hang my current session, but other users not affected while the operation running.
You were right, the problem is solved. We entered the IP address instead of the correct DNS name on some clients.
After replacing the IP, everything is working as expected.
For those facing the same problem: the script needs to be corrected. The ‘server_ssl’ setting works correct if it’s not passed as a string but rather as a Python boolean. Change Line 111
