Hi, I want to set an SMTP server/service within IIS in XP. However, last time I did this, the mail server was hacked by many spammers!! Any pointers?

Don't use Windows for this....especially IIS. Seriously. Microsoft does server stuff quite badly. If you need a workstation go with a Microsoft OS. If you need server functions, go with Unix, Linux, Solaris, or even Apple (with OSX). I set up an SMTP server with Linux last month and it wasn't too difficult. It was the first time I'd ever tried it, and everything has been working pretty well. No hacking, no reboots, no bugs, no computer science degree.

....but wait, there's more..... There is a program called SpamAssassin that works pretty smoothly with Sendmail. I used it along with a blacklist, and it's very effective for preventing the delivery of spam. If you mean your server was being used by spammers, welllll.......you shouldn't have it set up as a relay. But then again I can't imagine that using IIS on Windows XP gives you any real configurability or control. To use an analogy...would you hop up a Yugo and enter it into the Indy 500? Yeah, you could drop a V8 in it, but what would you do about the aerodynamics and handling? So why are you trying to use Windows XP as a mail server? I think you're putting a lot of effort into something that just can't work well.

So is also IIS a bad Web Server? Sould I move to a free flavour of linux for servers?

IIS is a truly horrible web server and it's easily hacked. You don't have to use Linux to get a better web server though. Apache is used on the majority of the world's webservers and is also freely downloadable from apache.org. It runs on several OS's including Windows. If you're just running some personal site where server up-time isn't that critical you can get by with running Apache on Windows. If up-time and stability is an issue, you should consider Linux. I have a Linux box at work running Apache and it's been running without a reboot for over a year and a half. Please don't interpret my statements as a damnation of Windows...I use Windows. What is true though is that while MS makes a pretty decent workstation operating system, its server class system is not server class.

I disagree. Microsoft's SMTP server isn't that bad. Provided you take precautions, you'd be ok. However, Exchange is really the MS's true email solution. SMTP is very watered down. IIS's webserver is also improving. Not a slam on the other web and mail servers out there at all. Most of what you hear with MS getting nailed is the patch is out there, and so many servers didn't have the patch when the attacks came. MCSE, MCSA Messaging, baby!