http://www.simflyers.net/support.htm
Question:
I have purchased World Airports. Can I download an FS 2004 update for this?
Answer:
A FS 2004 compatibility patch is available - it depends on which version of World Airports you have.
"Just Flight" version:
The update is available from the Just Flight website
www.justflight.com. If you have registered World Airports you will find it in the list of your registered products in section "Support".
In case you need further assistance with that please check back with
helpdesk@justflight.com - they'll be able (and happy) to help
"Strategy First" version:
The update is available from the Strategy First website
http://www.strategyfirst.com/en/games/addons/