This problem is driving me nuts.
 
I have a 128MB USB thumbdrive (Soyo Cigar Pro2, shows up as "Prolific USB drive" in devmgr). Windows XP Home decides to "infect" it with a system restore folder set to use 93% of the drive space whenever I connect it. I disable system restore for that particular drive letter every time, but as soon as I disconnect the drive and later reconnect the drive, system restore discovers and "infects" it yet again...
 
I also have a External 80GB IEEE1394 drive that I use for manual backups that is victimized by system restore in the same way.
 
Short of turning off system restore completely, is there something I can do to tell system restore to leave these two removable drives alone forever?
 
I don't know that it matters, but the thumb drive is formatted FAT32, and the external firewire drive is formatted NTFS.
 
I haven't spent a great deal of time debugging this, but I think it may be a case of system restore "forgetting" after a system reboot that I set it to not use those drives