I see 3 downloads for AE CS6. I downloaded one
" AfterEffectsTrial-12.0.1-mul-AdobeUpdate "
and when trying to run it get this message
" Update Failed
Updates could not be applied
This patch is not applicable for you. Please check updates from the Help menu in your product to see a list of the latest updates available.... "
I'm running Mavericks, and at this point AE wont even open.
That is not an update for After Effects CS6 (11.0). That is an update for After Effects CC (12.0).
Just choose Help > Updates within any Adobe application and install the updates automatically that way.
If you're not willing to use the auotmatic updater, then use the manual download for the After Effects CS6 (11.0.3) updater. Do not use the After Effects CC (12.0.1) upodater; that is not for your version.
I tried a different update and it seems to be installing now.