This morning I opened File Explorer and found that all my folders and files in the Documents section were completely gone, as was everything in the Pictures section. I've read over the advice given to others who've experienced this, and carried out all those suggestions, to no avail. This is what I've tried so far:
Check Recycle Bin (nothing there, nor should there be; I didn't accidentally delete the entire contents of my Documents and Pictures)
Check for hidden files and folders (none)
Check OneDrive (there were a few older items there, but none related to the hundreds of missing files and folders; note also that I long ago turned off syncing to OneDrive, and it remains off now)
Check for being signed in to a temporary account (nope, I'm signed in to my Microsoft account)
Check for recent Windows updates (no updates had been done recently, except for Windows Defender two days before; I also just ran a virus scan and no threats were found)
Run a recovery program (I ran Recuva and did a deep scan that took almost an hour; it found no documents, but I also got this message: "Failed to scan the following drives: \.\HarddiskVolume2: Unable to determine file system type")
Until today I had no idea one's entire collection of docs and pics could simply vanish without a trace. Any advice beyond what I've already tried would be much appreciated. (Note: I have the latest version of Windows 11 on a 2 year old HP laptop.)