I recently went back to my parents' (overseas) and found my backup (WD 3TB My Book). I got all hyped, it enclosures the treasures from my golden years. Sadly, it doesn't seem to work properly anymore —even when it was stored in a dry fresh dark place (for over a decade).
When I plugged it in the computer it was able to read it without issue. Knowing the fragility of the situation, I started to copy the whole drive instead of browsing it. After 10% or so it stopped working. I re-plugged it in a different port and retried with similar results (with a progress equally low). After that it became hard to read it so I stopped —I didn't want to damage it by forcing a huge transfer in an unstable condition.
My current plan is to try to access it from some Linux distro and, if I can read it, copy by folders (everything is organized in main categories).
I don't think my old friend has much time left for trial and errors, so I'd like to check with you. I'm sure you'll have better ideas than my current barbaric plan.
Thank you, this is important for me, and I highly appreciate and advise.
The most common failure with external drives is the electronics, not the drive itself. Safest bet is to pull the drive out and connect it to your computer directly, or if you only have a laptop then you'll need a SATA drive enclosure or adaptor.
If you really want to play it safe, consider getting a drive cloner like this one and a matching new drive. If you suspect the old drive is damaged/failing, then the absolute safest thing is to not do any work on it directly.
Seagate distributes a freeware called Seatools which is pretty good for checking drive health (should work on any modern drive, not just Seagate branded ones).
TestDisk and PhotoRec from cgsecurity are probably the best file recovery tools out there. If you clone the drive and you aren't able to browse the files on it or access them, try using these tools to recover any undamaged files (and even the damaged ones) from the clone. I wouldn't recommend running this directly on a suspect bad drive except as a last-ditch effort.
And if the original disk is damaged and you aren't able to get the files you want from it with the above, then you can try SpinRite which in some cases is able to make unreadable drive sectors readable again. This isn't free, but it has a very good reputation for working on hard drives.