Issue Split Domain Name Routing, Hosted Exchange, DMARC

[Terence Channon]

We have a sender, call it @xyzdomain.com and their emails are not getting through to exchange-user@abcdomain.com that are using Hosted Exchange via a split domain name environment. Here is what happens.

1. @xyzdomain.com sends to exchange-user@abcdomain.com
2. Email first gets to linux server
3. Email then gets forwarded to exchange-user@forward.abcdomain.com (this is what we use for the split domain name alias. - So in PLESK we have the user exchange-user@abcdomain.com set to forward to the exchange-user@forward.abcdomain.com
4. The email never gets to the exchange user - there is a 'no signing table match for" error that is generated.

When we send emails to regular-user@abcdomain.com, everything gets through ok.

The 'forward' seems to be messing with the DMARC policy for the sender, @xyzdomain.com. Any ideas on how we can fix this in PLESK? Any configuration suggestions? Questions about the set-up? Is this a potential bug in PLESK and how it sends out emails/forwards?

FYI - emails sent from @yahoo, @aol, @gmail for instance are able to get delivered to the end-user/exchange-user box without issue.