Warning:Wrong type argument: window-configuration-p, nil

[duplyhan]

Any help is appreciated...

When I was intend to look up some words, it comes this WARNING:
"Wrong type argument: window-configuration-p, nil" in the minibuffer

And the info in the Message buffer as below:
"pylookup-mode-quit-window: Wrong type argument: window-configuration-p, nil"

My Env:

Emacs23.4 in CentOS5.8 in VirtualBox

[starenka]

same here

Debugger entered--Lisp error: (wrong-type-argument window-configuration-p nil)
  set-window-configuration(nil)
  pylookup-mode-quit-window()
  pylookup-mode-lookup-and-leave()
  call-interactively(pylookup-mode-lookup-and-leave nil nil)