I have tried solving this problem by googling and browsing superuser.com, but haven't found a viable solution yet. I'm running Windows 7 btw.
I somehow got Arduino to recursively create folders named "libraries" within the parent-folder called libraries. Somewhere down the path, there are also some library-files and now I can't delete the damn thing. The path is so deep, that I can't enter it all the way down to the files. Every time I try to delete the files I get an error saying either something like "path too long" or "Directory not empty".
I have tried deleting it through the cmd.exe using:
del /S /Q libraries\* rmdir /S /Q libraries
I also tried robocopy, as some threads mentioned this as a solution.
robocopy ROBCOP libraries /s /mir
And finally I have tried using a tool called DelinvFile. This tool started to delete the folder, but after deleting ~6000 subfolders, it stopped with the error "Directory not empty".