I set variable "org-file-apps" like this: (setq org-file-apps '(;; default (auto-mode . emacs) ("\\.mm\\'" . default) ;; ("\\.x?html?\\'" . default) ("\.x?html\'" . "firefox %s") ("\\.pdf\\'" . default) ("\\.pdf::\\([[:digit:]]+\\)\\'" . "okular -p %1 %s") ;; extras ("\\.chm\\'" . "kchmviewer %s") ;; TODO open CHM file with external program. )) But when I open a CHM file, Emacs does not open it with "kchmviewer", just open CHM in Emacs. What's wrong ? -- E M A C S s e l o h c t t n i p a t f a r t e o l [ stardiviner ] ^^&^^ {I hate all of you ! Leave me alone} IRC(freenode): stardiviner \\ Twitter: @numbchild \\ GnuPG Key fingerprint >>> 9BAA 92BC CDDD B9EF 3B36 CB99 B8C4 B8E5 47C3 2433