I have a Ubuntu 20.04/Windows 10 setup. Both OS'es boot from - and store application settings etc in - their own partition on my SSD, while most of my personal data is stored on a separate HDD (physically inside the laptop casing, but for all intents and purposes an external hard drive).
I almost never use Windows. Today, I opened it to test something for what (I think) was the first time since I bought the computer 6 months ago. In Windows, I found I could not access any files on the shared HDD - it was listed as empty, and the 'Properties' tab confirmed that all its space was free. I did not do anything else to the directory in Windows.
Concerned, I booted back into Ubuntu, and found that there too the HDD was blank (it contained only an empty recycle bin and a 'System Volume Information' directory). I unmounted and remounted, ran ntfsffix, tried mounting other partitions... but everything came up empty. Curiously, gparted did list that the HDD had about 170 GB in use (which sounds about right for what I know should be on there). But this still gave me no way to actually access the files.
I am now restoring from an external backup with Duplicati, so all my files should be alright, but I am very concerned. How could this possibly have happened? How can I keep it from happening again if I ever need to use Windows again?
