How do I fix a "Wrong Type Argument: listp," error when trying to access remote file using tramp?

Question

I am unable to access remote files in my usual way:

C-x C-f [server]:[path][file]

and am thrown this error: Wrong Type Argument: listp, [[server]:[path][file]

I'm not even sure how to debug this further.

any help is appreciated.

edit:

output when trying to debug:

Debugger entered: nil
(progn (debug) (ido-mode t) (progn (ad-add-advice (quote completing-read) (quote (foo nil
 t  (advice lambda nil (if (boundp ...) ad-do-it (setq ad-return-value ...))))) (quote 
around) (quote nil)) (ad-activate (quote completing-read) nil) (quote completing-read)) (define-key global-map [(meta 120)] (function (lambda nil (interactive) (call-interactively
(intern (ido-completing-read "M-x " (all-completions "" obarray ...))))))))
(if (fboundp (quote ido-mode)) (progn (debug) (ido-mode t) (progn (ad-add-advice (quote
completing-read) (quote (foo nil t (advice lambda nil (if ... ad-do-it ...)))) (quote
around) (quote nil)) (ad-activate (quote completing-read) nil) (quote completing-read)) 
(define-key global-map [(meta 120)] (function (lambda nil (interactive) (call-
interactively (intern (ido-completing-read "M-x " ...))))))))
eval-buffer()  ; Reading at buffer position 16103
call-interactively(eval-buffer)
(lambda nil (interactive) (call-interactively (intern (ido-completing-read "M-x " (all-
completions "" obarray (quote commandp))))))()
call-interactively((lambda nil (interactive) (call-interactively (intern (ido-completing- 
read "M-x " (all-completions "" obarray (quote commandp)))))) nil nil)

recursive-edit()
debug(debug)
implement-debug-on-entry()
*  ido-find-file()
call-interactively(ido-find-file nil nil)

And this from my init.el:

(require 'ido)
(if (fboundp 'ido-mode)
(progn
  (debug)
  (ido-mode t)
  (defadvice completing-read
    (around foo activate)
    (if (boundp 'ido-cur-list)
        ad-do-it
      (setq ad-return-value
            (ido-completing-read
             prompt
             (all-completions "" collection predicate)
             nil require-match initial-input hist def))))
  (define-key global-map [(meta ?x)]
    (lambda ()
      (interactive)
      (call-interactively
       (intern
        (ido-completing-read "M-x " (all-completions "" obarray 'commandp))))))))

Answer 1

Check what command C-x C-f is bound to (use C-h k). Is it the standard binding find-file? (It doesn't sound like it.)

If not, check its interactive spec. The command is expecting to receive a list as argument, and it is instead receiving (what looks like) a string.

This is the interactive spec of find-file:

(interactive
 (find-file-read-args "Find file: " (confirm-nonexistent-file-or-buffer)))

If the interactive spec of your C-x C-f command, like this one, has a non-string as its argument, then you can either M-x debug-on-entry THE-FUNCTION, where THE-FUNCTION is the function called for the argument (find-file-read-args, in the case of find-file), or wrap that argument so that the debugger is invoked:

(progn (debug) (WHATEVER-WAS-THERE-BEFORE))

Either way, the debugger will open for the interactive part of reading the file name, and you can walk through the debugger to see what goes wrong.

But probably you can figure out the problem just by inspecting the code -- the interactive spec. The argument to your command (whatever it is) is expected to be a list, but it is a string.

I would start by seeing what happens with a local file name. Do you get an error for that too?

Another thing I notice is that the error reports an extra [, in front of what you say you typed as input. That should provide a clue too. What you think it is reading is not what it has read.