Using CHKDSK
To use chkdsk, open a command prompt, but be sure to run it “as Administrator”. When the black box opens, enter the following:
chkdsk c: /f
and press <ENTER>.
You will receive a prompt about checking the disk when the system starts. Be sure to answer Y. Then, shut down the system and restart it.
To check a different drive, substitute the appropriate drive letter. You won’t have to restart, but may have to dismount the drive.
For those of you who prefer a graphical approach, see here,