Email address assigned to group bounces back

New Contributor

Odd problem that isn't getting resolved by MS Support despite much effort on my part.  I created a new group (call it MyGroup) and then assigned it the email address  When I send test messages to that address, they get bounced back with an "address not found" error message.  However, when I assign the same address (after deleting the group) as an alias for one of the users, the address works fine.  By all appearances, the settings look correct.  When I display a list of the groups, it shows the correct email address in the list.  The group is set up that same way as other groups that have email addresses assigned to them.

Assistance here would go a long way to restoring my sanity.  Thx

5 Replies

Hey @Nestor Holynskyj,


I am guessing your GUI is not working as intended, so instead do some investigation/testing in powershell.


Once you have it assigned to the group try this in powershell.




If it comes back with not found, then something is not working in the GUI when you are trying to create the group.


Based on what type of group you are referring too, you could then also try to create the group and associate the email address through powershell directly.


O365 group -


DL -




We had something similar happen, but it wasn't an Exchange problem.


If you're sending using the full Outlook client to run your tests, make sure you're not using a "cached" email address from the AutoComplete list, especially if this email address used to be an alias and is now going to be a full DL.


Information about the Outlook AutoComplete list -


We had this happen when we moved DLs from being hosted on-prem to hosted in the cloud. There is a unique ID that changes in the background, even though the email address is the same. The error message is a similar "address not found" error, which was VERY frustrating to track down.

Adam:  Thanks for the response.  Turns out that Occam's Razor still holds true.  The solution ended up being stupidly simple.  When I set up the group, I didn't check off the box that allows people outside our organization to send messages to that address.  Checked the box and all is well!  As Homer Simpson would say, "Doh!"

Thought you would have been testing from an internal address, that bit of info would have helped ;). Anyway, they really should update the NDR to let you know hey you aren't allowed to send to this address, not this address doesn't exist! lol!

Just glad its working! Good to hear!