Mail server listed in black list

[stergiosnik]

Hello All.

The IP address of the mail server is listed in a black list so the mail messages are rejected from the recipient's mail server.

I delisted the IP once but today I see that the IP is black listed again.

How can I detect which email account is using the mail server in order to send out spam?

Can I configure something on Exchange 2003? Is there any special software that I can install on Exchange 2003?

How would you solve such a problem?

Thank you in advance.

Stergios.

 

[58sniper]

I would search this forum. There are a lot of helpful hints that should resolve the problem.

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

http://www.ucblogs.net/blogs/exchange/

 

[nicksheppard]

I'd start by asking the blacklisting service why you were blacklisted to begin with. That could provide a clue.

I'd say the three most common genuine reasons for being listed are:

1. You have an open relay on your mail server (check your smtp settings in the exchange system manager/iis) to see where you allow e-mails to be relayed from. If it's been misconfigured you might be allowing e-mail to be sent through your mail server from any external location.
2. There's a system on your internal network which is infected with a trojan/virus which is sending the e-mail. As a very basic check freeze your outbound e-mail queue in the system manager for half an hour or so and check how many messages are being sent through the server. Scan your clients and make sure they're clean.
3. If you are using some sort of mailshot software within your company and sending out large bulk e-mails, or you have some overly complex e-mail signatures or footers with lots of links and other junk that might get you flagged.

Hope this gets you going in the right direction.

If you reply, how are you sending your e-mails, are they going from your server directly (dns search) or are they being pushed to a smart host. This second method may provide a way around since you can pay another company to deliver mail on your behalf. You'd have to pay for this service.

Good luck.