I've been having a problem with a power user in Outlook 2019. When the user exits Outlook 2019 it stays in memory and consumes 20-30% CPU in the background and does not exit for at least 20-30 minutes. Eventually it exits from memory as well.
I've done the following to troubleshoot this problem, but I haven't found a solution to it yet.
Disable all add-ins.
Repair OST file using SCANPST tool.
Removed all mailboxes from Outlook profile except for the default one.
Recreated Outlook profile.
Recreated the user profile.
The user is a power user, so he has more than one mailbox attached to his Outlook from Exchange Server. There's nothing fancy in the configuration either.
This happens to his profile whether he is logged in on his desktop or his laptop. The ost size is approximately 50GB, but even after recreating his profile many times with limited accounts his Outlook always keeps running in the background.