the downloaded folder to your FS2004/Addon Scenery directory. Launch Flight Simulator 2004. Open the Scenery Library. Add Area and select the HECA folder.
How to Find the ARMI Project Cairo International Airport HECA FS2004 Link armi project cairo international airport heca fs2004 link
📁 If that link ever breaks, just Google: "ARMI Project HECA FS2004" file and look for results from Flightsim.com or AVSIM Library . the downloaded folder to your FS2004/Addon Scenery directory