Dolby Media Encoder 4.0 and earlier requires Rosetta to operate on Apple silicon Macs. macOS 27 (Golden Gate) does not include Rosetta by default, and upgrading to macOS Golden Gate uninstalls any existing Rosetta installation. As a result, Dolby Media Encoder will not start on any Mac running macOS 27 Golden Gate.

Manually reinstall Rosetta from Terminal using the following command:

softwareupdate --install-rosetta --agree-to-license

Once Rosetta is installed, Dolby Media Encoder will be able to open.

You can also go to Applications > Dolby > Dolby Media Encoder, right-click on the Dolby Media Encoder icon and click Get Info. Inside Dolby Media Encoder Info window check "Open using Rosetta". This will trigger Rosetta installation. Follow the system instructions. 

Note: If you have already upgraded to macOS Golden Gate, you will need to run this command even if Rosetta was previously installed, as the macOS Golden Gate upgrade removes it.

For the latest information on Dolby Media Encoder compatibility and system requirements, visit Dolby Customer.