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#11
It may be too late, but here's another two cents worth of advice. If the external drive is in warranty, it will have to be sent back to be replaced, so your data is toast with that option, if you can't get it off before RMAing it.
So what I suggest, assuming your external drive is a 3.5" model, is to open it up. Google your model series, and you may even find a YouTube link which shows how to open it, if it's a difficult affair. Most, if not all the 3.5" drives in an external enclosure merely plug into bog-standard SATA power and signal connectors on a miniscule circuit board at the end of the enclosure, such as are in your PC, i.e., the MB SATA signal connector on the MB, and the SATA power supply cable coming from your power supply.
If you can get the HDD out of the external case, AND IF IT DOES NOT HAVE A SOLDERED/ONE PIECE SATA/USB, etc., connector, then just connect the HDD to your MB SATA, and power supply connectors. Then it will just be another (or a different on ... if you are disconnecting one to allow this to be used) drive hard-connected, like your current WD and Seagate. This may allow you to get more than the few - 15 minutes you currently have, to get your data off before the drive finally rolls onto its back with its feet in the air! And it will.
Now, this will void your warranty, although WDD was sympathetic to a friend of mine when he opened up an external HDD to get his data off before sending it to WD for replacement. He had a heat problem inside the case, and this is what may be happening in your situation. At any rate, if your data is very valuable, as you say, sometimes difficult times call for non-traditional solutions.
BTW, most 2.5" WDD 1tb externals have a solid/different connector on the back of the drive, part of a different drive board, so that this trick (connecting internally within a PC) won't/can't work. In your situation, though, nothing ventured, nothing gained.