A couple of weeks ago, I went to a shop because I needed to print some posters. I had my file on a USB stick, which the clerk inserted on a Windows 10 laptop. After a minute, he told me he could not do anything with my file.
When I checked, I saw the problem: some nasty Windows malware replaced my folders with .exe files. Windows asked if my drive needed to be repaired. Since I knew I was not going to print anything that day, I went forward with the repairing process. The result? The .exe files were gone but my files were not back.
At home, I plugged the USB stick to my Linux computer and, sure enough, I could see all my files plus the malware-generated ones. The malware had inserted copies of itself in every folder and sub-folder while making my original files invisible to Windows. What a nostalgic feeling!
After I deleted all the copies of the malware, I searched for the way to make my files and folders visible again on Windows.
It turns out that Windows does it like this:
attrib -H -R -S /S /D F:\*.* (F stands for the letter assigned to your USB).
Well, it seems that Windows malware keeps being as effective as it was back in the times I used that OS. Some things never change!