I probably need to give you more information.
I ran GSX successfully in FSX-SE on Tuesday night. I didn't change anything, but on Thursday morning when I used FSX-SE, having loaded the flight (aerosoft airbus, UK2000 EGKK, ASN weather with soft clouds etc) I pressed Ctrl-F12 and no GSX menu appears but the error notice referred to in the other thread.
I followed your instructions as best I could in the other thread, uninstall, download brand new GSX, install, check the antivirus exclusions etc etc. I can see the fsdreamteam folder in FSX-SE, and GSX and LSGG are there. I have done this 3 times, and also downloaded the Addon Manager separately. I have an Addon Scenery folder, but no folder in FSX-SE called "Addons". I haven't deleted anything.
However, GSX is not working in FSX-SE.
I would appreciate help please