I have read some other threads regarding this same issue, some sound quite similar.
External Hard Drive - connected by USB port 2.0
Windows recognises that USB Mass Storage Device Drive has been connected - however it does not show in My Computer as a drive.
Computer Management - Disk Management does not list it as an available drive.
Device Manager lists it as a drive - and device is working properly.
How do I get access to the drive to recover of anything from it using any data recovery software?