Choose a file... ... from here (relative path and file name):
fileadmin/Note: the file list in your text-file must contain file names with absolute path and the string "/uploads/"! E.g.
/home/web/mydomain.com/uploads/pics/testfile.gif
Go to "Admin Tools -> DB check -> (Database) Relations" and copy the "files with no references at all" into a file in your fileadmin-folder
and this extension will delete that files for you.