This happened to me onetime. Not neccessary. Check autoexec.bat and config.sys, make sure you don't have any drivers loaded for the hard drives. If there is any, remove them and restart windows. Hope this works.
its because your computer some how is using real mode drivers instead of protected mode that are for windows. when a windows 9x computer winds up using real mode drivers it will show a window on the perfomance tab in the properties of "my computer icon". Like above post go into autoexec.bat and config.sys and REM out the lines
how about ControlPanel/SYSTEM click on the offending drive and go to UPDATE drivers and install the correct one instead of that dos driver! ?? wouldnt that work?