[O] No Export Tag Not Working?

[Aric]

Hello,

I am certainly doing something wrong with regards to the EXCLUDE_TAGS. I 
believe the default is noexport. I have the following in a subtree:

*** subtree
:PROPERTIES:
:TAGS: noexport
:END:
  blah, blah, blah. 

The subtree is still exported during html export. I have tried to look at the 
option 'org-export-exclude-tags' but it appears to be an unknown variable in 
my set-up. Is there some module that must be loaded to get this option? Am I 
tagging the subtree incorrectly? Must #+EXCLUDE_TAGS be set in every file?

Using Org 8.2.5c.

Thanks in advance, Aric