EMERGENCY: 4 Win XP Pro Computers in a Business Office Hooked up to a Dedicated Server:

I'd like to know the absolute best software out there for Anti-Virus and Spyware Removal for a server and business office. I'd love to know how to work it, if you could give me a quick run-through, and if I could get a free trial and purchase it. My brother's business office is in danger of being shut down, because someone on their ISP is reporting their IP addresses are sending out spam. The ISP said if they got one more report, then they'd shut it down in 24 hours. They run their business through computers, and not having Internet would crush the company. I suspect their computers have been hijacked and are now being used as zombie-drones. If you guys could help me pick a couple programs that I could run from their server, or on all machines individually (Whatever you recommend), I would be eternally grateful.

I have an hour or two before I have to be down at the office.
However this is extremely urgent.
I'm at home, looking for programs, but I know you guys could
help me pick the best. We have to get this right, and done tonight.

They are asking for my help, and I've never worked with a server before.
I am fairly advanced in Computers, and I am willing to try.
Thank you in Advance.

This post has been edited by hysteria: Oct 30 2006, 03:02 PM

anyone??

this is an emergency! please help