This thread indicates all the known solutions for missing menu items under the "Addons" menu:
http://www.fsdreamteam.com/forum/index.php/topic,7545.msg62899.html#msg62899As an alternative, you might try to install the latest Couatl 3 Public Beta, here:
http://www.fsdreamteam.com/forum/index.php/topic,11796.0.htmlWhich might work better on your system, since it requires different system libraries, which hopefully are correctly installed on your system.
I have noticed that some of my sound files have gone missing around the same time as GSX and Addon Manager.
This seems to indicate the problem which is affecting our modules, is also affecting another addon that is supposed to play sounds.
You can activate the Simconnect diagnostic mode to see what's wrong with your system. Open notepad, and copy the following text:
[SimConnect]
level=errors
console=1
RedirectStdOutToConsole=1
OutputDebugString=1
; file=c:\simconnect%03u.log
; file_next_index=0
; file_max_index=9
Save the file as SIMCONNECT.INI in this folder:
Documents And Settings\YOUR LOGIN NAME\Documents\Flight Simulator X files
At the next launch of the sim, you should see a text window with diagnostic message, that should tell what's going wrong. Let me know what you are getting, so we can have an idea what's happening. Only the first 15-20 lines are important. If the scrolling goes too fast, try again and use the "Pause" key on the keyboard to read the first lines of the screen.