Forum Discussion
Exchange - Undeliverable Emails
I have a single Microsoft Exchange account (to allow me to sync addresses, calendars, notes etc across a range of windows and android devices).
The email for this account is mailto:xx@domainname.onmicrosoft.com.
I also have a number of email adressess at my company domain : mailto:xx@domain.com
If I try to send emails from mailto:xx@domainname.onmicrosoft.com to any email address at mailto:xx@domain.com I get an "undeliverable" message stating :
"Your message to xx@domainname.com couldn't be delivered. xx wasn't found at domainname.com."
Any suggestions as to why this is happening would be most welcome.
Thanks
SB
5 Replies
Hello sjb66
Could you please check the email delivery using the online Microsoft tool : testconnectivity.microsoft.com and see the exact issue you face
Thanks,
Manu
Which server is generating the NDR? It might be a simple case of you having a matching contact within your directory, causing the message to be routed incorrectly. Also, run a message trace: https://docs.microsoft.com/en-us/microsoft-365/security/office-365-security/message-trace-scc?view=o365-worldwide
Thanks for the suggestions. I had a look at the https://protection.office.com/ message trace utility and I wasn't able to run it but I think it shows where the problem is.
I'm logged in as mailto:xx@domainname.onmicrosoft.com but the default queries in the message trace section all refer to mailto:xx@domainname.onmicrosoft.com clearly the system is somehow confusing the two accounts.
My primary Microsoft account (for Microsoft 365, Onedrive etc) is under mailto:xx@domainname.onmicrosoft.com . the Exchange account is (because it has to be) under mailto:xx@domainname.onmicrosoft.com .
Hi, is the xx@domain.com added to your Office 365 tenant as an accepted domain please, or is it residing elsewhere, such as an on-premises Exchange Server?
PeterRising There is no connection between them at all apart from the fact I access both of them via Outlook on Microsoft 365.
mailto:xx@domian.com is on a 3rd party supplier, web host server, and is not an "exchange" server.
