Black lists?

[Rob R.]

hello;

When a member of the company sends a message to various
domains, he or she will recieve the following error
message:

Your message did not reach some or all of the intended
recipients.

Subject: E-mail black list
Sent: 8/16/2004 2:28 PM

The following recipient(s) could not be reached:

recipient@e-mail_address.com on 8/16/2004 2:28 PM
There was a SMTP communication problem with
the recipient's email server. Please contact your system
administrator.
<our.server.org #5.5.0 smtp;554 denied by
gorbs>


Does anyone have any suggestions as to what is going on
here? my best guess is that gorbs is a black list (but I
can not find it.) We have recieved this error with
several different domains, and with different users.

Thanks;

Rob R.

 

[James L.]

I'm gettting the same complaint from my clients recently, although my
mailserver's IP is clean shown in openrbl.org. What's GORBS?

 

[CKP Admin]

I'm gettting the same complaint from my clients recently, although my
mailserver's IP is clean shown in openrbl.org. What's GORBS?

I am receiving a similar message contained below:

"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<server.domain.com #5.5.0 smtp;554 denied by gorbs>"

Any information would be appreciated. First thought was making a
change to our reverse lookup records. (IP to name) We had very
recently upgraded to a new exchange server with a new name. This had
no effect. Any other ideas?