Steam players may receive an "Age of Mythology: Retold requires at least Windows 10 to run." message if the Steam's compatibility settings need to be adjusted.
To adjust the settings, follow these steps:
- Browse to your Steam installation (Usually C:\Program Files (x86)\Steam\)
- Right click on Steam.exe (or bin\steamwebhelper.exe), choose Properties
- Click on the Compatibility tab
- Uncheck any boxes that are checked, and click Apply
- Double click on Steam.exe to launch Steam.
- Re-test the issue.
These steps can also be found on Steam's Support site:
Steam Support :: How do I disable Compatibility Mode? (steampowered.com)