trouble deleting files from an external drive
Open Terminal
Drag folder you want to delete onto the Terminal icon in the dock
Type cd .. in the new Terminal window in order to move to the parent directory.
Type ls to find out the exact name of the files/folders in the directory.
Type sudo rm -r filename to delete the file/folder 'filename'. Be careful to type the correct name.


Dragging files onto the terminal icon does not work. You will need to drag the parent directory onto the icon.