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.

The AgeIIIESOPatch_Full will allow you to access multiplayer services without routing through the deprecated ESO service. It is important to install the patch for additional stability and reliability in the multiplayer environment and avoid issues accessing multiplayer matches. Download and install the patch manually using the steps below:



Download the patch by clicking the button below.


Installation Steps

  1. Download AgeIIIESOPatch_Full and then run the application.
  2. Click Patch Game File in the Age of Empires III Patcher window that opens.
  3. Click Open to start the installation in the default Age of Empires 3 folder.
    1. If Age of Empires III is not installed in the default location, navigate to the folder where age3.exe is saved.
  4. Age of Empires III Patcher will show that the game is patched.

When Age of Empires III is opened again, a User Account Control prompt for age3.exe will appear. Click Yes to start the game.


Q: Can I still use the same sign in information after download the patch?
You will continue to use the same sign in credentials for multiplayer regardless of eso.com availability.
Q: Is the patch required to play the game?
While the patch is not required at this time, it is strongly encouraged to download in order to ensure smooth gameplay if eso.com is unavailable. In the future, eso.com may be permanently removed, at which point the patch will be required to continue accessing the game’s multiplayer services.

Additionally players who have not downloaded the patch will be unable to play multiplayer matches with those who have.

Q: Why is there a CRC Mismatch error on some multiplayer matches after downloading the patch?
This message appears when a match is hosted by a player who has not installed the patch. We are working hard to make sure that all players are aware of the patch to increase reliability and to avoid issues accessing eso.com in the future.

If you experience any issues downloading or using the patch, please reach out to our Support team at aoesupport@microsoft.com for assistance.