Protools 10 using .aax version of NI plugins, won't work. How do I switch it back?

Hey guys,

Recently I wiped my PC and did a fresh install of Windows, PT, and my plugins.
So far so good, except when I updated my NI plugins, they no longer worked in PT. In the plugins menu, some of them say .aax beside them. How do I switch PT back to the old plug ins?