There are certain addons one may need to run before, during or after the loading of FSX. For example, the pmSounds from Project Magenta is one msut-have feature I normally run alongside with the FSX.
Instead of clicking the addon’s program icon every time, I just put the addon in the following format:
Add the above module to the exe.XML file
under C:\Users\<your name>\AppData\Roaming\Microsoft\FSX — the directory where fsx.CFG is stored.
NOTE that this module must be added to the exe.XML file while FSX is NOT running. Also, the path of the program (where the file is stored) must be clearly stated.
Then, from the next time you run FSX, the addon will be automatically loaded.
The following Security Warning will appear at the first time FSX loads the new addon module. Just click [Run] and continue to install it.
The same module format and insertion method applies to many other third-party addons. But NOT for those addons (such as REX and Shade for FSX) which needs to modify the contents of FSX. In other words, these addons MUST be run and completed before the loading of FSX.