Another way if needed .
DOS's Scandisk can sometimes do it better .
Toggle F8 ( when , verifying DMI pool message comes on ) or Press Ctrl during bootup , depends on your computer , choose Command prompt only ( NOT Safe mode Command prompt ), then at the C: prompt , type Scandisk /Surface & press Enter .
When finished , type win & press Enter .
http://users.iafrica.com/c/cq/cquirke/scandisk.htm