So I have a 500gb Seagate HDD that, after powering down my computer one day, stopped being read by ANYTHING. It's not a mechanical error that I could diagnose; it spins up and down quietly and makes no strange noises of any kind, and continues to spin as normal for as long as it's got power. The BIOS on two different computers and an HDD->USB adapter do not detect it. I've tried using SpinRite 6 and Puppy Linux to try and find the drive; neither see it.
I'm totally lost as to what I can do at this point. I've read countless amounts of information about what it could be, but most are about obvious mechanical errors (eg: Clicking, grinding, no spinning at all), but this drive just stopped working out of nowhere and as far as I can tell works fine mechanically. I don't have hundreds of dollars to get it professionally recovered, and I don't need the drive itself; I just want to be able to recover some amount of data off of it. I'm very close to trying the old freezer trick, but that's definitely a last resort.
When I powered down my computer, it was for Windows Update... could that have done something to some part, somewhere?
And yes yes, I know "You should have had backups"; I was planning on setting up some level of backups in the near future before this happened. Too late now.