I had some issues with creating a new user in our domain. The exchange mailbox of his was corrupted and I had to remove and recreated the profile.
It's working fine now, except the user cannot receive internal emails, the sender always gets the error message
IMCEAEX-O=FIRST+20ORGANIZATION_OU=EXCHANGE+20ADMINISTRATIVE+20GROUP+20+28FYDIBOHF23SPDLT+29_CN=RECIPIENTS_CN=John+20Smith@myDomain.local
#550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ##
The email address for this and any other of our users goes like this: [email protected] . myDomain is an external mail provider, but the same address is used for internal mails.
Sending mails to [email protected] works on the other hand, but this would be confusing to use, just for this one domain user.
I've checked the other topics with the #550 error, but none of the solutions there worked for me (no address book isue/NK2 file issue)
I'm a bit at a loss on where the mail name gets resolved for internal routing, or whatever causes the issue.
**I've noticed that the faulty user has 2 entrys in the attribute "ProxyAddresses", one for the external address, one for the local. Had to add the local one via exchange manager, because it was missing. But on all clients, and the global address book, the new entry is still missing. I forced and globaladdresslist update, but it's still not showing, might this be the issue? **
It actually is related to the autocomplete cache (indirectly) for those internal users trying to send email to this user. You'll need to do one of two things:
Or
Have a read here:
https://support.microsoft.com/en-us/help/2807779/imceaex-non-delivery-report-when-you-send-email-messages-to-an-internal-user-in-office-365-dedicated
The article references Office 365 but is relevant for every version of Exchange.