|Simple answer is don't waste any more time on this. You could care less what drive letter it is.|
complex answer is there is a partition on that machine that really does have a few nt files on it. There will alway be a C: drive in xp.
again not worth the effort to figure out.
"Best Practices", Event viewer, host file, perfmon, antivirus, anti-spyware, Live CD's, backups, are in my top 10