I am missing AAC codec after running update to media encoder (CS5)

I cant export h264 video since every time i try to do it I have a message "AACA codec missing".

This happened after running updates from the HELP button sub menue.

There is not even an option in the media encoder scroll down menue with AAC codec and I used to have it all the time for many years.

Can you help me restore my software to the state it was before the updates or just fix this codec issue?