I am indeed missing both menu's in my "Addons" menu in the Sim. I have removed my antivirus and disabled Windows Defender and then Removed the VC++ Libraries (2005 SP1, 2013 and 2015). Then, I reinstalled all the required VC++ Libraries in the order of first 2005 SP1 x64 then x86 etc. After that I restarted the system just like it was said on the linked thread. After restart, I installed GSX. During the Installation I saw the installer saying "Matching remote file, skipping update." I don't know if that is normal. Anyway, I installed GSX again, restarted my PC, and then fired up P3D, still no GSX or an Addon Manager in the Addons menu. I only see SODE and thats it. I don't know what to do next.