run command prompt as admin

cd to the location of folder

DEL /F/Q/S *.* > NUL    (this deletes all files all the folder structure)

used cd.. to navigate to parent folder

RMDIR /Q/S foldername (this deletes the folder and all subfolders)

DEL /F/Q/S *.* > NUL

/F — forces the deletion of read-only files.
/Q — enables quiet mode. You are not ask if it is ok to delete files (if you don’t use this, you are asked for any file in the folder).
/S — runs the command on all files in any folder under the selected structure.
*.* — delete all files.
> NUL — disables console output. This improves the process further, shaving off about one quarter of the processing time off of the console command.

RMDIR /Q/S foldername

/Q — Quiet mode, won’t prompt for confirmation to delete folders.
/S — Run the operation on all folders of the selected path.
foldername — The absolute path or relative folder name, e.g. o:/backup/test1 or test1