Maybe these articles will help:
You might also consider using a utility like TrashIt.
FWIW, error -1407 is corresponds to "Expected a folder, got a file". You may want to consider running Disk Utility to repair/verify your drive(s).
I have some very old files on my laptop that I cannot delete. The file type is: Unix Executable File.
The type is bogus. It's what Finder says when the file has no filename extension, nor file type signature.
When I attempt to trash these files, I get error msg: The operation can’t be completed because an unexpected error occurred (error code -1407).
The error is "Expected a folder, got a file". Possibly bogus too.
The simplest way to get rid of them (if they're not too many) is in Terminal. Here's a short description of Terminal
To delete one of your files, in Terminal, at your prompt, type
Then drag the file on the Terminal window. Its path should be inserted on the command line. (Make sure it's the right file. The rm command is not undoable.) Finally, press Return to execute the command. The file should be deleted whatever it is. If there's an error, copy the message text and paste it here.