"Tip: If you are asking for help to troubleshoot a computer-related problem, please be sure to include all the necessary information (ie: operating system, model number, hardware, software, etc) that will help others identify your problem for a speedy resolution."
While rarely caused by hardware, here's the most common Knowledge Base article for Windows 98 that does that -> http://support.microsoft.com/default.aspx?scid=kb;EN-US;152404 Read the link to article "273017 ScanDisk Runs Even Though Windows Shut Down Correctly" if need be.
Bob
For some reason my pc started to run scan disk after
a normal shut down.Every time i start the computer
after a normal shutdown it runs,and it's not the
short scan it's the complete scan.The first time
it did it i let it run all the way thru but after that
i just cancel.I have disabled it but i would like to
fix the problem. Any ideas? Im running a 750 athlon
with win/me. Thanks

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