I am at my wit's end with a problem that I am having. I recently had to replace a hard drive and of course as a result did a format/ reload. Everything was ok for a while, then Windows [98SE] just totally freaked out. Programs would not run, illegal op errors, fatal exception errors, you name it. Second format/reload. Everything works fine for a while, now similar problems, except programs do at least run for a while before everything starts crapping out, AND system now mysteriously reboots. I had an older version of Norton System Works and recently upgraded to System Works 2005. I don't particularly trust speed disk or optimization wizard, but I have used them out of desperation. I use Win Doctor a lot--it is not finding any problems, scan disk has not found any problems. HDD was low level formatted and burn in and testing was done at least twice before Windows installation using max blast. There are no drive overlays, since that is not needed and a total waste of system resources. I downloaded a shareware program called BurnIn Test and ran it, thinking maybe i had a flaky processor or memory issues--no hardware problems found. I downloaded and installed a shareware program called Registry Repair Pro for the heck of it--126 problems found and I do not trust that diagnosis when WinDoctor is not finding any issues, especially when I cannot stop that program from running at startup, even though i have unchecked it in msconfig--that is cause for concern about the trustworthiness of that program. Symptoms have not changed since installation of that program, so I don't think it has created new problems or complicated existing problems. No conflicts found in system properties. No known malware/adware/spyware problems. I don't yet have XP reloaded b/c I need to get this issue resolved first and I don't particularly like the idea of a 3rd format/reload. All hardware and software t'shooting results are ok, but it has to be a software conflict. I am stumped.