User can't send mail to 1 other user

HCL Domino Domino Forum
1

2 users are on the same domino server.user A can’t send mail to user B.

User B can send mail to user A.

All other Lotus users can send mail to user B.

Error messagge when sending mail :

“No route found to domain example. from server DOMINO01/example. Check DNS configuration”

Why check dns configuration ?

Mail shouldn’t leave the server since both users are on the same server.

Both users use the Lotus server to send mails.

Server 8.5.3

2

Subject: check USER A’s personal address book and their recent contacts list

They probably have that user in there with an incorrect address