Server Problem

Please HELP! the server where I work is sending out spam somehow. The system is a NOVELL/Groupwise 6.5 We have 19 workstations each with their own hard drives. We all run Spybot and AdAwareSE on a regular basis. We have ETrust Antiviral software installed on the server and on each workstation. We have been black listed everyday with SpamCop. Because of this we can't communicate with our clients and vendors. What do we need to do to get this horrible situation under control? Thanks in advance for any help!

setup groupwise to not allow annonymous senders from the SMTP port 25 which is probably set without security. By allowing only authenitcated users from your corp. net should stop annonymous users from using your server to send mail.

Thanks, I'll give that a try if I can figure out how to do it. My days of Novell experience go back to Dos and then I wasn't what you would call a super user, I barely managed to keep the ediitorial department running. I do know that port 25 is not secure, I went to a sit called grc and ran the scan they offer that checks for open ports. That one turned up.

Well, my co-worker and I have been searching and we haven't come up with any info on how to secure port 25 on our server and we are black-listed again. This is driving us both nuts. Can anyone help? Can we be helped?