Question : 550 5.7.1 Unable to relay for [email protected]

We are using the email notification in BE 11d to notify us of failed and completed backups.  This was working fine until last week.  Now we have stopped receiving remote email notification from one of our client sites (running the BE exec 11d server).  He is a configured recipient and is receving notifications internally.

Running Exchange 2003 on 2k3 server standard Sp2

When I try to test through telnet - I get the following:

220 mail.remoteclient.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.4675 ready
 at  Tue, 6 Jul 2010 09:21:44 -0700
EHLO test.com
250-mail.remoteclient.com Hello [192.168.69.11]
250-TURN
250-SIZE
250-ETRN
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-8bitmime
250-BINARYMIME
250-CHUNKING
250-VRFY
250-X-EXPS GSSAPI NTLM LOGIN
250-X-EXPS=LOGIN
250-AUTH GSSAPI NTLM LOGIN
250-AUTH=LOGIN
250-X-LINK2STATE
250-XEXCH50
250 OK
MAIL FROM:[email protected]
250 2.1.0 [email protected] OK
RCPT TO:technician@ourdmainname.com
550 5.7.1 Unable to relay for [email protected]m


Domain names have been changed obviously.  I also tried sending to my personal email account with the same results.  I'm not sure what has changed.

if additional information is required, please let me know and I will be happy to provide. it.

Answer : 550 5.7.1 Unable to relay for [email protected]

add the IP address of the servers that you want to relay to exchange servers in the allow relay list in SMTP virtual server properties