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Almost everyone has a USB drive(pen drive, thumb drive) now a days due to it's decreased cost. Each time when you insert a USB drive Windows might give different drive letter if you are using more than one drive at once. To avoid this confusion, I have a great tweak which lets you assign a unique drive letter to all the USB drives. Here is what you need to do:
1.Insert your USB drive in USB port.
2.Type, "diskmgmt.msc"(without quotes) in Start Menu Search box or in Run dialog box and hit enter.
3.In the Disk Management window, right click on your USB drive and select 'Change Drive Letter and Paths'.

4.Next, click 'Change' option from the available options.
5.Choose a drive letter for your lovely drive.
6.Click 'OK' and then, 'Yes' for the confirmation message.
Warning: Move the contents of the drive before changing the drive letter as some application might not run properly.
