I've installed the emacs-app via port, and there was no problem with Latex Preview Fragment in a buffer at all. Now, using the M-x package-list-packages, I've installed the latest org 9.0.3, then the latex preview is not working at all. It comes with following error: org-create-formula--latex-header: Symbol’s function definition is void: org-export-get-backendError during redisplay: (eval (mode-line-mode-name)) signaled (void-function mode-line-mode-name) The version I'm working on is like this: Org mode version 9.0.3 (9.0.3-elpa @ /Users/ysong/.emacs.d/elpa/org-20161224/) GNU Emacs 25.1.1 (x86_64-apple-darwin16.5.0, NS appkit-1504.82 Version 10.12.4 (Build 16E138)) of 2017-01-09 Is this known bug or is there something I need to do more?