Effective September 1, 2021, the multiplayer service for the 2007 version of Age of Empires III: Complete Collection currently on Steam will no longer function. The critical factor driving this change is that the ESO domain on which this multiplayer service currently resides is no longer under Microsoft’s control and it will be repurposed by its new owners on that date.
To continue accessing the multiplayer services: We have created a patch that points to a new backend owned by Microsoft that you must manually install prior to September 1, 2021. Due to the age of the title, we have no way to automatically apply the patch for you and you will have to come to our website download linked below to apply the patch manually. We apologize for any inconvenience this may cause.
Steps to download and install the patch can be found in the Age of Empires III: CC ESO Patch article.
If you have other questions about Age of Empires III (2007), also known as Age of Empires III Complete Collection, the best place to ask is to visit one of our official discussion channels. There you will find other knowledgeable players.
Note: Our Support team is unable to assist with ESO account issues in Age of Empires III (2007).