found this in their forums site
Forums
The problems with Win2k are too numerous to list here, Brian. The rash of CodeRed/CodeRedII/Nimda infections ALONE this year have swamped our RCCs and overloaded Curtis and myself to the point where we began to seriously consider the blocking of Win2k from the network.
Windows2000 was *never* intended for the home user, which Microsoft itself would categorize all users on ResNet; it was intended for coporate use in an environment that had a centralized administrator/IT group that was responsible for securing, auditing, and updating those boxes on a regular basis. Stability issues aside (don't get me wrong, I know that 2000 is indeed more stable than 9.x/ME), there is no real reason for any home user to be running 2000.
In addition to the IIS infections mentioned above, ResNet users became the unwitting hosts of a very massive dDOS attack that lasted almost 2 months. What was significant about these attacks?
Every_single_compromised machine (50+) was found to be running Win2k and was compromised through an extremely basic oversight...a blank administrator password.
In talking to the majority of the owners of these machines, almost 90% didn't even know what an administrator password was! Why should these people have been running Win2k to begin with?
Here are just some of the (basic) things that need to be done to a Windows 2000 computer to ensure a minimum level of security...remember, this is only a *basic* list, and a partial one at that:
-Disable the guest account (now done in SP2 and higher)
-Eliminate any unnecessary accounts
-Create 2 administrator accounts (with a strong password)
-Rename the administrator account
-Replace "Everyone" group with "Authenticated Users" on all file shares
-Strong passwords for all user accounts
-Use NTFS on all partitions
-Always run a currently updated Anti-virus program
-Install the most current Service Pack immediately after installation of the OS
-Check windowsupdate.com on a regular (at least once per week) basis for the latest patches and updates for known exploits/new vulnerabilities.
Please keep in mind that I am NOT a huge fan of everyone installing XP either (When we last checked, there were nineteen critical(!) updates for WindowsXP Pro following the default installation), but the potential for a catastrophic compromise of the computer is indeed reduced under XP in comparison to 2k.
As far as Home vs. Pro when discussing XP, again there is not a huge reason for residential/SoHo users to run XP Pro. There are very few features that Pro has over XP...Group policies, roaming user profiles, RIS service, and scalable processor support constitute the majority of them.
If you've made it to the bottom of this post, then congratulations...it turned out to be much longer than I intended, but hopefully that sheds some light on our reasons for this policy.