My pen drive's size has reduced from 4Gb to 2Mb, what can I do to fix this problem?

Click start control panel administrative tools computer management disk management right click on your drive select properties click tools you should see click check now click start two boxes
automatically fix files and scan for and attempt recovery of bad sectors place then a tick in both boxes then select check now start
you might tick one box then return after its finished the first repair then return and tick the second box you should not do anything while the chkdsk utility is in progress any input may damage this drive
I found that you get best results by ticking one box then returning after it has finished then tick the other box
then you might have restore it to its default status

Right click on usb drive select properties you will have an array of options

Select the hardware option then select your drive properties policies

restore defaults

In XP

Right click on your drive select properties then on customize restore Default in W 7

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