Need to shutdown Port 25 on user machines but not the exchange server to stop spamming
Posted on 2007-03-20
I have a client that is running Small Business Server Regular Edition. They have a Linksys BEFSR41 Router. There are running exchange on their small business server. I am running Trend Micro Client Server Messaging Security which is not picking up any viruses. The only way I know they have virus issues is that they keep getting blacklisted as Spammers. I am going to purchase a new watchguard router in the future but I need to shut down port 25 for all the local machines (there are 8 of them 6 XP Pro and 2 Windows Vista) and leave it open on the exchange server. I am hoping this will stop what ever machine that has a virus from spamming.
My question is, how as of today can I kill the local machines from having access to port 25 while leaving the server access. I don't think it can be done with the linksys router. The port filtering there seems to kill all access to port 25 including the server. I could be wrong though.
Is there some sort of login script or just a simple configuration I could make to each machine to stop access to JUST port 25. There are only 8 machines so it would be no big deal to go to each of them.
I want to do this today so I can submit them to be delisted.