Hi EleTi.
The reason that you can't delete a folder is because it is
not empty. You may have checked for topics in them but I bet there
is an image or baggage file that is still there.
The first thing you must do is restore the folders from your
Recycle Bin. Never delete or move files/folders from outside RH
unless you want to create all sort of confusion inside your RH
project. Next go through your baggage files, image, multimedia and
style sheet folders inside RH looking for any left over
files.