Hi guys, Suppose you're using a 3rd party SMTP gateway that is redirecting mail to your exchange 2007 server, yet as part of the redirection is mangling the rcpt to: header and dropping the domain part, how would you persuade Exchange to ignore the missing the domain part and accept the mail? The redirecting server is leaving the local part in tact: RCPT TO:<mr.quetzalcoatl> and exchange responds with: 501 5.1.3 Invalid address The SMTP gateway in this example is providing anti-spam and content filtering services and only conditionally forwarding certain qualifying mail through to the exchange server, but it is screwing up the recipient address as a side effect. Exchange 2003 is able to map a recipent which does not have a domain part to a default domain. Can 2007 do the same?

Answering my own question, it seems that setting the default domain on the smtp connector sorts this out.