FSX Steam Edition installs and runs as Administrator. When we use Ideal Flight with FSX:SE we set Ideal Flight desktop shortcut icon to Run as Administrator, that way when IF starts FSX:SE it will start as Admin. If FSX:SE is already running then Ideal Flight will join communications with FSX:SE as Admin.
FSX:SE installs SimConnect versions for FSX Gold and FSX:SE only. Ideal Flight uses those. However, in the SDK folder we also have the SP1 version and that should be installed as well in most FSX Systems. Ideal Flight can also use SP1. If the system is new and FSX original was not installed then it is recommended to install SP1:
C:\Program Files (x86)\Steam\steamapps\common\FSX\SDK\Core Utilities Kit\SimConnect SDK\LegacyInterfaces\FSX-SP1\SimConnect.msi
Run SimConnect.msi there to install SP1.
We can use settings in the Ideal Flight Setup to select SimConnect versions. Also there we can use a function in the menu to show which SimConnect versions are available on the system.
Finally we can use FSX:SE with IF without Run as Admin by using the Setup menu item to stop the 'Force Run as Admin' with FSX:SE. However when we update steam files the Admin requirement will be attached to FSX:SE again, requiring IF setup be run again so as to choose to stop that Admin requirement.