#5.7.1 smtp;550 5.7.1 Unable to relay for Error

[kopja]

Hi

I am getting this NDRs from one user only, and send to one specific external domain only.

user@external.com on 10/23/2006 4:02 PM
You do not have permission to send to this recipient. For assistance, contact your system administrator.
<FQDN (internal) #5.7.1 smtp;550 5.7.1 Unable to relay for <user@external.com>>

The user can send OK to any other external domain names.
Any body has any pointer as to what it might be?

The NDR shows my local SMTP server generating it, but all the internal users have permission to relay/use the SMTP server. Also the user can send email fine to other domains as well.
I do not have any recipient policy in place, so nothing stops users from sending to anybody they want.

I also looked up the external domain IP via DNSStuff.com,
and it resolves OK through my local connection. I can ping/tracert it fine.
Using Win03 and Exch 03.

Any help would be greatly appreciated.

 

[Marcs41]

Try to contact them to see if they accept your domain. If they have filters in place, you cannot get around that.

One easy way to check is to (temp) use your ISP as SmartHost. If it passes then, ask the targetted domain to allow you.

Marc
_{If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all.
Free Tip: The F1 Key does NOT destroy your PC!}