I have 4 computers on a router and 1 running linux... the rest my family uses. They have to format like every month because of viruses and spyware and they have anti-virus.

Is there anyway for me to scan for viruses before they get to their computer without making it dedicated to doing only that?

Thx,
Zach

Following the instructions in my post in the thread below to secure the windows machines and you should be ok. I ran WinME for almost 5 years and never had to reformat or reinstall.

Secure your system and keep out spyware, viruses and popups

you can run a transparent proxy server and scan using clamav

I am usually running either Smothwall or IPCop as a firewall on an old PC.
I feel this helps all around to cut down on intrusions, Linux or Windows either one.
This would not stop self installed spyware or email viruses in Windows.

I agree with craigevil's list of do's and don'ts. I have many people ask me the same question. The things I stress are

1) Use a Mozilla browser (Mozilla suite, Netscape or Firefox), preferably Firefox
2) By all means, do NOT use any P2P file-sharing programs. Those are spawning vats for viruses.
3) Use ZoneAlarm on the Win machines and pay attention to what programs are requesting access. If you don't know what it is say deny.
4) Use an antivirus that is updated daily and make yourself a schedule for scanning (once a week, once a month,twice a month). I recommend no less than twice a month

What's your setup like? Do you use dial-up, cable or dsl? Is it possible to put the modem on one box and have the other machines go through there, using NAT, to reach the internet? On my 5-machine home network with dial-up, I have one linux box with a modem and running c-mserver (masqdial server) configured to allow only ips on my network to access. My other machines are configured with static ips and dial through that linux box. The only machine that gets the ip from my isp is the one with the server. Your ip address is something to protect.

Regardless what the setup is, the best place to protect each machine is at each machine itself.

Since this seams to be more of a Windows issue I'm moving you to General.

i've been running win2k for more than a year, with no antivirus, no firewall... (appart for the one on the adsl router) and i have never had a single issue with it, no viruses no malware, no spyware nothing!!

Set up is 4 computers all attached to a router that goes to cable internet. I was hoping I could protect the windows computers maily from viruses through my machine but not routing them through my machine. I will be looking into the proxy server stated twords the top of the thread but have never delt with one nor really know much of what it is. I haven't done much metworking aside from the simple home setup thing I have.

I'm a linux homer like most people here, but what sites do you all go to and get hammered by all the viruses? My machine has xp and its firewall and I haven't had any problems at all...

Are viruses mainly from porn sites and warez and all that crud?

My setup is two linux machines, one dualboot with linux and win2k, one win2k and one win98. In the 15 years that I've been using computers none of the computers I use now or owned before have had serious problems. A friend once gave me a CD with an installation program that was infected with a virus. Norton caught it right away. He got the file using either Morpheus or Kazzaa. Another friend recently had his Administrator account on his win2k trashed because of massive infection by one low-risk virus. He didn't know until too late because his antivirus definitions were 3 years old. He'd been downloading lots of mp3 and mpeg files with WinMX.The popular Winamp program comes with the common WildTangent spyware/adware. Ad-aware can easily remove this. I've read recently that spyware can be easily picked up from free screensaver sites. Mostly the eZula and/or some search bars. They can be trickier to remove becaue you have to use Google to find instructions, remove the files and edit the registry to remove the self-reinstalling entries.

A good rule of thumb is: If you're downloadin from a reliable, trustworthy site the files will be fine. But if you're getting free screensavers from Billy Bob's Shack of Free Warez - WATCH OUT!

Use ZoneAlarm
Use antivirus that's updated daily
Use Ad-aware, Spybot or both

I agree completely...I think a big chunk of users download all the spyware filled crud and then get frustrated...if you don't download illegal stuff, you probably won't have a problem with a messed up machine no matter what OS you use.