Let me make it simple.
In Windows you have folders (directories) which store your files. Here’s a hypothetical folder:
Inside that folder you copy all of your favourite pieces of music. Now as long as you can find your music, you’re happy but let’s assume that you want to be organised and categorise your music.
So Music is the main folder and the other genres of music are sub-folders. If you wake up one day and want to listen to Jazz then you can play the contents of the Jazz folder without needing to individually find everything in one cluttered main folder as in my first example.
Previously AxCrypt could only encrypt the main folder (first example).
Now AxCrypt can encrypt recursively (folders within folders) like in my second example.
The reason it can be dangerous is that if somebody encrypts the “Windows” folder on the C:\ drive you risk locking yourself out of your OS (Operating System) because you’re encrypting critical system files.
If however you’re encrypting your Music folder or your Tax returns (within yearly sub-folders) then you’ve not got a problem. But don’t go encrypting critical folders like Program Files, Program Data or Windows.
The moral of the story is be careful. Encrypt only your documents, photos, videos etc. Don’t encrypt folders which contain software programs.