Since the original publisher (Vivendi/Sierra) no longer exists in its original form, official "key recovery" services are generally unavailable. Digital Re-release:
If you are installing the game from a physical disc or a digital retailer like GOG.com , you will need a valid product key. empire earth 3 key code
If you are trying to recover a lost key using a key-finder software (like Magical Jelly Bean or ProduKey), look for this format: look for this format: