Hi @Waleed Waleed ,
some users are in O365, and we migrated some users to new Exchange 2019, after the migration the search box in outlook is not working for all users,
Do you mean you migrated some users from o365 to Exchange 2019, and after that, both users in O365 and Exchange 2019 cannot search in Outlook?
Any difference if you switch between Exchange cached mode and Online mode?
Can this issue be replicated in OWA?
Considering that migrated users also have issue with the calendar app in Teams, I'd recommend trying to re-run the HCW with a full hybrid and see if both issues can get fixed.
In case the issue persists, please understand that usually we only focus on one question per thread, so it would be best if we mainly discuss the search problem here, while for the issue with the calendar app in Teams, you can try to open up a new thread using corresponding tags. Thanks for your understanding!
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