some users mail boxes got migrated from USER@domainA.COM to different doman i.e user@domain B.com
that users @domainA.com (non migrated) are getting undeliverable message when they send to users @DomainB.com( both migrated & non migrated), Please see the error message .
As per the error message it is trying to find email address “@domainA.com” for users who are in @domainB.COM.
They are able to send email from their webmail . We tried outlook level troubleshooting like cleared autofill cache and pulled the recipient name from GAL, but no luck
is it something to do with LegacyDN attribute of contact object in domain A.COM?