|If Windows is detecting the circuits of the external drive's case correctly, in Device Manager - USB controllers there is an entry for a USB Mass Storage device or similar. |
You get a separate similar entry there if a USB flash drive or a card reader is connected
If you have more than one entry, RIGHT click on it and select Properties - you can usually easily tell from what it says there which device it is.
"...The hard drive has gone dodgy before, but that was a USB Port fault ...."
External drives require a lot of power, and they won't work properly in all possible USB ports you can plug them into.
The USB connection of the external drive requires that the USB port you plug it into can supply 500ma, the max. USB spec.
The front USB ports in a desktop case may have inadequate wiring to them. If you have USB ports higher up on the front of the case, the wiring for them may be inadequate, or the multiple ports may be ports in a hub that connects to one USB port directly connected to the mboard - that type of hub does NOT work properly with all USB devices.
If you have the drive plugged into an external hub that is the type that has multiple ports that connect to one USB port directly connected to the mboard, the external drive and many other USB devices may not work correctly, even when the hub is a "powered" one that has an external power adapter connected to it. The same goes for USB ports on a printer, scanner, keyboard, etc. which are ports in that type of hub.
The external drive can get enough power from any USB port directly connected to the mboard on a desktop mboard, and directly connected to the mboard ports on most laptops. If you have a plate in a desktop slot space with USB ports, that will probably work with an external drive, if the wiring to the mboard header is adequate. The ports in a PCI USB controller card can all supply enough current. Some laptops can't supply 500ma from any of their directly connected USB ports - in that case you have to connect an external drive to TWO USB ports, or if the external drive is 2.5", one USB ports and have an external power adapter plugged into a jack for that on the drive.
A 3.5" external drive requires a USB port connection that can supply 500ma and that the external power adapter that came with it is plugged into the external case and is powering it.
A 2.5" external drive may require TWO USB connections, or a connection to one USB port and have an external power adapter plugged into a jack for that on the drive.
Some 2.5" external drives come with two cables to connect to two USB ports on the computer end, or a USB Y cable - a small USB connector on the case end, two regular type A connectorson the computer end, or they may have one USB cable and a jack on the case you can plug an external power adapter into, but they usually don't come with the power adapter.
An external drive may not work correctly when plugged into a port on a laptop's PCMCIA (PC Card) USB 2.0 controller card, or a port in an ExpressCard USB 2.0 controller card, even if the card has a jack for connecting an external power adapter to and you connect one.
If you're SURE the external drive is plugged into one or two USB ports it should work in according to the above info, and if the circuits of the external case show up as a Mass storage device in Device Manager, then it's likely the hard drive inside the case has failed, and if you were to remove the hard drive and connect it properly internally directly to a desktop computer and test it with the hard drive manufacturer's diagnostics, you could confirm that.
"The hard drive has gone dodgy before, but that was a USB Port fault and caused the hard drive to randomly corrupt files. It was relatively easy to scan the device and repair the bad sectors, ..."
"That was your key to stop using that drive. "
USB connection problems can cause data to become corrupted, but they can't cause the drive to develop bad sectors. All drives have a small number of bad sectors, but you don't find any bad sectors for a drive that is not failing, because the automatic hardware/logic routines of the drive swap them with spare good sectors as they are encountered or develop with time. Visible (findable) bad sectors indicates the drive is failing and all the spare good sectors have been used up.
If you use the Seagate Seatools diagnostics with the hard drive (it won't detect the drive when it's in the external case), the Maxtor drive can be repaired by Zero filling it (you will lose all the data presently on the drive) ONLY if the Long test finds only a small number of LBA errors - the Long test quits when it finds more than 99 LBA errors, because it's extremely unlikely in that case that the user can fix the problem with any software.