Scandisk is automatically launched by systems that run the OSR2 version of Windows 95 -- the standard operating system on most PCs purchased in the last year -- if the system was previously turned off before Windows 95's Shut Down process had finished properly.
Scandisk looks for stranded fragments of lost files. Windows 95 is constantly moving files between the hard disk and memory, even when applications are idle. If power is suddenly shut off while a file is being written to disk, that file may get corrupted, and Windows 95's bookkeeping system may lose track of which hard disk sectors belong to that file. So an improper shutdown can mean permanently losing a file or hard disk space.

Change Windows 95 boot-up options by editing the msdos.sys file

My advice is to always use Shut Down and avoid these problems altogether. But if you really don't want Scandisk to run, here's the fix. Using a text editor, open up the hidden text file msdos.sys located in your root directory and add the line Autoscan=0 under the [Options] section. You can also set other boot options in msdos.sys. Or change Autoscan and a few other boot options with the Tweak UI applet, available from http://www.microsoft.com/windows/windows95/info/powertoys.htm.

The free Tweak UI utility shuts off automatic Scandisk operations

- Kirk Steers
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