I ran into an interesting issue today, something that is an old leftover from early mail systems.? I was trying to e-mail my hosting provider back on a support ticket I had opened with them, but when I replied I got a bounce message saying my mail was rejected with the following message:
Your message did not reach some or all of the intended recipients.
Subject: RE: myticketnumber]: message subject hidden for privacy reasons
Sent: 2/8/2008?3:16 PM
The following recipient(s) could not be reached:?myhostingprovidersemailaddress?on?2/8/2008?3:14 PM
The recipient could not be processed because it would violate the security policy in force
< smtp1.myproviderdomainname.com #5.7.0 smtp; 554-5.7.0 Reject, id=26006-18 – BANNED: multipart/mixed 554 5.7.0 | application/ms-tnef,.tnef,winmail.dat>
So I did some digging online, and tested some things out.? I found that even if sending from OWA I still had this issue, so I knew it was a server configuration option I needed to look for.? The provider I am dealing with was quick to blame me of course, but my server config has not changed in years.? So I think they changed something on their side recently with the way their helpdesk processes mail, and thats what caused this issue.?
To resolve it, I went into my ESM, under global settings, internet message formats properties and changed the options to never use Exchange Rich text.? After applying this change, the issue was resolved and mail flow has been restored.?
I personally don?t like making server config changes due to problems with sending mail to just one outside recipient, but I deal with my hosting provider a lot and its a hassle to have to reply from a different mail account.?