Spam relay - Exchange 5.5 1

[Overdoos]

Hi all,

I'm running an Exchange Server 5.5 (with a Trend ScanMail Viruswall). On that system we have internal mail of different countries coming in over a VPN but mail from the outside world is coming in over the public internet.
Recently I found that spammers are testing our system to use it as a relay. I thought that we where pretty safe, but apparently we are not. (Of course I blocked their addresses, but they keep coming) Can someone help me? I don't really know what to do anymore.

 

[bp1169]

Here are some websites that can help you secure that relay.

http://schneider.technion.ac.il/Microsoft/Exchange/Relay.asp

http://www.exchangefaq.org/security/0002.php3

Hope this helps.

 

[bp1169]

When you have it secured you can test it to see if is still an open relay at

http://ordb.org/submit/

 

[Overdoos]

Yes, that helped me a lot.
I'm still testing if I got where I wanted now, but at least I know what I'm dealing with and I've got some ideas on how to stop it.