We have 2 Exchange Organisations, One Exchange 2007, One Exchange 2003. We are receiving winmail.dat attachments from the users in the Exchange 2003 domain. This has only occured since the migration to Exchange 2007. All of the Exchange 2003 users in Question have either a Contact or a MailEnabled AD object in the GAL of the Exchange 2007 domain. Should Exchange 2007 be converting these Winmail.dat attachment into readable emails? Thanks

Hi, This might help: http://support.microsoft.com/kb/290809/en-us Leif

Thanks for this but I feel that there is something not happening because the external users are represented as a MailUser or Contact. Its as if Exchange doesn't try and do the conversion because it thinks they are an internal mailbox.

do you have an SMTP connector in your E2003 organization? mail is under curcumstance's handled different when going through a SMTP connector

I'm not sure. I don't think so. They just send all their messages across the internet.

What format are they sending the message in? Make sure they are using HTML.

if both org's are on the internal network you can create a SMTP connector with the remote domain address space. on the connector you can specify to always use HTML. with this mail between your org's will travel on your LAN only and alwaysbe HTML formatted without users need to do anything