My W7 64-bit machine stopped recognizing USB external drives and thumbdrives. I found a post on the internet about some systems not having the required USBSTOR.inf file. My machine was missing this file so I created one and copied the recommended text into it - file is attached. My machine will now recognize my Seagate FreeAgent GoFlex external drive (which it didn't before) but just gives the same 3-beeps when any others are connected.
Are there additional entries in the usbstor.inf file that need to be made for other drives? Is there another file that needs to be created or modified