My emacs version is 
GNU Emacs 24.5.1 (x86_64-apple-darwin13.4.0, NS apple-appkit-1265.21) of 2015-04-11 on builder10-9.porkrind.org <http://builder10-9.porkrind.org/>

I’m using elpa, and org-mode is updated to the latest version

Org-mode version 8.2.10 (release_8.2.10 @ /Users/mac/.emacs.d/elpa/org-20160215/)


I’ve tried to add require ‘ox, and it’s not the case. Maybe it is caused by a mixed installation. How to solve this problem? Thank you!

Junxiang








> On 18 Feb 2016, at 19:15, Eric S Fraga <e.fraga@ucl.ac.uk> wrote:
> 
> On Thursday, 18 Feb 2016 at 18:44, 童俊翔 wrote:
> 
> [...]
> 
>> and when I perform C-c C-e p x, the error showed as: 
>> 
>> org-org-link: Symbol's function definition is void:
>> org-export-custom-protocol-maybe
>> 
>> How to solve this problem? Thank you for your help!
> 
> Maybe (require 'ox)
> but more likely the result of a mixed installation?  What version of org
> are you using?
> 
> 
> Thanks,
> eric
> -- 
> : Eric S Fraga (0xFFFCF67D), Emacs 25.0.91.1, Org release_8.3.3-619-gca1fb8