I despise NIS. In the firewall section you want to allow tcp 25 out and tcp 110 in most likely. Your mail provider should be able to tell you what ports you need. Sorry - I don't know the screens...

Just create local users with the same user/password as the users who are trying to connect.

Have you cleared his cache lately? In Internet Explorer go to Tools-->Internet Options and on the "General" tab click "Delete Files". You should also check to see if the cache size is small...under...

Usually you just paste the ip of the router into your web browser. Linksys is usually 192.168.1.1:

http://192.168.1.1

If you don't know the ip of the router you can try clicking...

Usually you just paste the ip of the router into your web browser. I think netgears are usually 192.168.0.1 network:

http://192.168.0.1

If you don't know the ip you can try clicking...

Sounds like the wireless. A "flapping" cable modem most likely would not be fixed by unplugging the wireless router although if timed right I suppose it might seem like it does. Either way a good...

What kind of network are you on? Campus? Cable? DSL? T1? What is the physical setup? Are you in a building with a lot of other people in your close proximity?

First things first: security
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