After leaving my XP Pro machine on for a day, I noticed it was running a bit sluggish. I checked the task manager, only to find the lsass.exe service was using up to 128,235k of RAM and increases 4k a second, and appears to have my processor usage up to 99-100%. I have been checking around, but haven't had similiar problems with error messages or the machine rebooting on its own due to lsass.exe. When I reboot my machine, the service starts back at around 4,450k, but then starts it's increase of 4k a second. Anyone have any suggestions? Processor is 2.53 GHz and have 512 MB RAM.