If you can get into Windows, then click on Start then Run and type in cmd and click ok. In the command prompt type in “chkdsk c:” and press enter. It will either run the check disk or it will tell you that it will run it the next time it reboots. If it tells you to reboot, then reboot the system and it will run check disk after reboot.
If you can not get into Windows, after the BIOS prompt is done, but before you get the Windows is starting message press F8 until a menu comes up. One of the options should be “safe mode command prompt”. Select that option, and when you get to the command prompt, type “chkdsk c:” and press enter.