I haven't been able to find a straight answer explaining this error anywhere. There are way too many potential causes and almost zero practical ways to actually fix it. Basically, you need an expert who knows their stuff—someone willing to dig through a million tiny details just to figure out where it all went wrong.
One thing I noticed is that most of the reports about this specific issue seem to be old, coming from people running outdated operating systems like Windows XP. Honestly, there’s no point in you listing your entire hardware configuration and software setup here. Usually, that's what we'd ask for to help you out, but at this distance, there's a 99.999% chance we won't be able to solve anything remotely.
Regarding your files: you can usually pull the drive out of any machine and plug it into another computer to grab everything, provided the drive itself hasn't completely died on you. Even if the drive is toast, there are ways to attempt data recovery, whether you try using specialized software or take it to the pros (I personally lean toward the pros) if those files are actually important to you.
Professional data recovery used to be insanely expensive, but even now, it's not always a massive hit to the wallet. It really just depends on how much those files matter to you.
https://www.bestbuy.com/site/tech-services/Just take it one step at a time. First, find someone who can pull the drive and try reading it on a different PC. Once you've done that and managed to save your data, then someone can start poking around to figure out what actually broke and what the next move should be.
