Hi @AATech ,
One particular Office 365 mailbox causes outlook to crash on multiple (including 1 brand new) computers.
Does the crash occur randomly or it can be reproduced by any particular steps?
Do you mean the mailbox is hosted on Exchange Online? Or you are running Exchange on-premise and by "Office 365 mailbox" you just meant the Office version? If the latter applies, I'd suggest try detecting and repairing corruptions on the problematic mailbox using the New-MailboxRepairRequest cmdlet.
Besides, please check the things below for further troubleshoot:
- When the crash occurs, check the Event Viewer on the machine to see if there's any relevant clues.
- Switch between Exchange Cached mode and Online mode and check how it goes.
- Open Outlook in safe mode(Press Win+R, type"outlook /safe",press Enter.) , see if the issue persists.
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