I put the usb drive in my system but its not working

[lamb01]

My usb drive is not working. I have tried it in several computers and none of them are working.
It was previously working. Can you help?

 

[phil22]

Check in Disk Management to see if it just needs a drive letter manually assigning to it:

Control panel > Computer Management > Disk Management

Look in the bottom-right pane.
If you see a ribbon with no drive letter or device name (and it may be labelled "Raw"), right-click it and choose "Change Drive Letter & Paths".
Click "New" and choose a drive letter from the drop-down box.

if it isn't visible in Disk Management it may have failed, or the USB converter board inside the enclosure may have failed (a common problem).
That can sometimes be solved by busting open the enclosure and removing the drive, removing the USB board, then fitting the drive either internally into a PC, or buying a third-party enclosure for it.