Matrix Games Forums

I bought EiA eight years ago. It has languished on my computer for some time.
Recently I wanted to play again, but when I launch the program I receive an
error message stating that the serial number is invalid. I would like to
reinstall, but cannot find the original installation file. The game is
registered to me. Is it possible to download the installation file again?

yes contact support

http://www.matrixgames.com/support/

Are you running Windows 10? I am and I get this error when I try to run the program from the Empires in Arms (Quick Start) icon. If I use the Empires in Arms Game Menu icon and then click on Play that works. Odd.