SMTP Relay Exchange HELP!

Can someone tell me what to put in the SMTP relay restriction area to get only my local subnet to use SMTP to relay? Everyone uses Outlook Express and POP3… don’t ask.

It asks for subnet and mask.

I’ve tried to put 192.168.1.0 and 255.255.255.0 and then no one in house can send email.

What do I put in there? I’m desparate. I want to do it via the subnet. I’ve also got some remote users that use AOL to connect, so I need to add their class A or B subnet as well, but that’s second. What do I do?

Help? Tell me what to enter…