When attempting the restore I get the log into Microsoft with the device code and it connects fine, hit next and veeam errors out saying Failed to open mailbox: gives the name Mailbox does not exist. I can guarantee the mailbox does exist.
Userlevel 7
+7
The account you're authenticating with is not granted with ApplicationImpersonation role. This permission is required to work with EWS APIs and access mailboxes.
https://forums.veeam.com/veeam-backup-for-microsoft-365-f47/restore-questions-with-mfa-t69254.html
Userlevel 7
+20
Do you have any more details on the error? This is very generic, so it is hard to give advice or help based on this message.
You may want to check the log directory for more details - C:\ProgramData\Veeam\
Otherwise, I would suggest a case with Support and checking on the forums as well - https://forums.veeam.com
**EDIT - I see Cary shared details so check those out**
Userlevel 7
+14
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