Will blcok port 25 really help to stop spam?
Posted on 2010-11-13
Wondering if block port 25 will really help to stop spam? As far as I know, if i setup the restriction on firewall, inside my network, all clients only able to communicate with my own mail server, and any other on the internet. But wondering if virus not able to send spam using my mail server?
And how usually virus send out spam on client machine? does it use telnet and the client machine act itself as a mail server and send out spam?