Your USB drive and another drive on the system are trying to use the same drive letter. Change the drive letter of your CD drive to something else.
Right click on My Computer-->Manage
Click on Disk Management under Storage
Right click on your CD Drive--> Change Drive letter and Path.
Click on Change and change the letter to somthing else (E).
I plug the flash drive into the pc and it reads "usb device" but when I look for the drive letter it doesn't exist.
Is there a way to turn on drive letters for external devices? The cd-rom shows as d: but the usb doesn't automatically turn up as any letter.
I can see the flash drive in the device manager but I don't see the letter.

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