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Exchange Online
Sending email to certain external email recipients expires. The email recipients are also a Guest Mail User invited to use/access SharePoint or Teams. Could the external email address and guest email be conflicting and causing our sending server to not resolve the external address? If yes, how can this be fixed without disrupting their SharePoint and Teams collaboration?
Had a ticket open with MS support. Had me run an extended trace report. MS support read the report and said the recipient server was not able to resolve the recipient email address. However, the IT team of the recipient server said it's our server that cannot determine the correct email address.
Ran another extended report but still running after many hours.
Reason: [{LED=420 4.2.0 Transient Failure during recipients lookup AmbiguousRecipientTransientException, Exception of type 'Microsoft.Exchange.Transport.Categorizer.AmbiguousRecipientTransientException' was thrown.} Reason: [{LED=550 4.4.7 QUEUE.Expired; message expired}
Any ideas?
Thanks,
Vince
Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Thanks Louis, this helps us understand better what we are dealing with.
To my knowledge (and this is based on 6 weeks of work with Microsoft, this can't be fixed with Powershell/User/Admin side. Still frustratingly waiting
AlexC2232,
A customer of mine has the same issue. A bunch of guest users were added december 20th. At the time the customer was in a car to a holiday destination and played with groups for sending a Christmas greeting. The customer couldn't get it working and deleted the group on december 20th.
Some of these contacts are now double-listed in Exchange admin center -> Contacts. When I try to delete one them I get the message "We are experiencing an issue with our server, please try submitting your request at a later time."
Could it be that already having had these contacts somehow caused the duplication?
How can I delete them? (not familiar (yet) with PowerShell)
Happy to help, Vince!
What Louis also experienced, if you delete the AzureAD GuestUser, the GuestMailUser in Exchange Online does not get removed.
This seems to be a synchronization issue between the AzureAD and Exchange Online directories.
Best, Alex
That's awesome AlexC2232! Top honors for you!
I did find the guest accounts previously but deleting them did not help.
However, since I have an open ticket with MS, I'll present these findings and see what they can do.
Thanks,
Vince