Multiple administrator Profiles created.

One of my servers is running 2000 server. I have it as a web server running IIS. It has been running successfully for about 6 weeks without reboot. However when I checked the document and settings folder I noticed it had created multiple administrator profiles…ie.
administrator.[machinename).01,
administrator.[machinename).02 etc to
administrator.[machinename).040.
It all appeared to have happened on the 28 OCT during the early hours. It has occured since. It appears that for some reason the os cannot find the original profile and as a result creates a duplicate profile.

Virus scans and patches are always updated. Any ideas what is causing this and how do I prevent it?