External hard drive isnt recognised

Clarifications

Because if not, then there is every possibility you have damaged some of the disk id files within the Freecom and your partition will now be gone. ;)

Freecom has several different types so it's harder as I have no idea of what you have.

But as it is not being picked up by the Found New Hardware start off with the obvious.

Look at the USB Lead for signs of Damage. If this USB Lead has 2 USB Connectors at the computer end they both need to be plugged in as the unit is drawing it's power from the USB Ports and these have limited 5 Volt Current available which isn't enough to power a External HDD over 100 GIG from just 1 USB Port.

If this unit has an external Power Adapter check it for both signs of damage and that is is actually producing the correct Voltage & Current.

Now if there are no obvious signs of Physical Damage you need to consider what has happened to this unit. If it has been left plugged in running it is more than likely that the Heat generated by the HDD has damaged the internal Electronics of the enclosure. This could be the USB to HDD Interface or it could be the actual HDD that has suffered Damage through ongoing degrading of the Electronics.

The most obvious answer if that is the case is to remove the HDD from the Enclosure and fit it is a suitable USB Enclosure that has been previously tested and see if you can access the HDD now. If the Data is Ultra Important you should just send the Drive to a Data Recovery House and let them recover any Data on the Drive before you do any more than look at the unit for signs of Damage. If you mess around with the drive you lessen the chances of recovering the data on it.

Col