If you are a user who will ALWAYS LOAD the default flight you have specified then DISABLEPRELOAD=1 is not neededand you know what is really silly?It takes the SAME AMOUNT OF TIME for FSX to 'boot' from a clean start and then load that default flight as it does not using preloadIts SIX OF ONE, ONE-HALF DOZEN OF THE OTHERIn case 1 where you are preloading when you start FSX for the first time after a system reboot... and use the default flight, the flight load itself is faster but the program BOOT is SLOWERIn the second case you are loading everything when the flight is selectedIf you ADD the time it takes to boot FSX with PRELOAD enabled to the reduced flight load time its the SAMETherefore, if you are a user who likes to CHANGE their location, to AVOID loading up files you DO NOT NEED TO LOAD into the memory and then RELOAD different files, then set the DisablePreload hookIf you are somone who ALWAYS uses the default flight, then do not set the preload hook but you are waiting the same amount of time to get to the runway. Your FSX program boot is slower even if your flight boot may be a bit fasterIts THAT simpleand since it takes the SAME amount of time from FSX boot to runway REGARDLESS of that hook, my advice has been to leave it DISABLED so it covers EVERYONE and provides the best CLEAN boot result regardless of the user wanting the default flight to load, or not

And to add to this, if the intention is purely to avoid loading or reloading unnecessary items on boot up, then consider making full use of the scenery menu options - primarily the `delete scenery cache on exit` button, which unlike DisablePreload DOES affect reboot time - it reduces it if you are in the habit of returning to the same flight each time - say after trying changes to driver settings or FSX menu items. However, it also LENGTHENS boot time if you don't return to the same scenario.And while you are there, simply uncheck any scenery areas where you are not currently flying - no point having all those detailed US sceneries active if you're only flying in Europe or Oz... These two factors ALONE affect startup times in the sim more than everything else put together. save for using an SSD and a proper, complete defragmentation of the FS drive.

You are missing something: That function is added by FSUIPC.

Thank you :(