Sharon, Nicolas Richard has pointed you to the reason for this problem. Re-installing all your packages will not help if the loaddefs in org has been generated using Emacs >=24.5.
Your best bet is to 1. remove the ELPA version of org, 2. download org directly from orgmode.org, 3. unzip it wherever you want and 4. add (add-to-list 'load-path "wherever you put org/lisp") to your .emacs or whatever initialisation file before you customise org's behaviour. By the way, you shouldn't break threads. It would make things easier if you followed up on previous emails that belong to the thread... -- : Eric S Fraga (0xFFFCF67D), Emacs 24.4.50.2, Org release_8.2.6-923-g233c11
