Before archiving an ODM project (or to clean up unused projects), ERS must be manually disabled within the project's setup workflow.
Open the left-hand navigation menu (hamburger menu) and select Projects.
Click on the affected Project Name, then navigate to the Setup tab.
Click on the EMAIL ADDRESS REWRITING section.
Select the "No, Maybe Later" option to disable ERS.
Click Next continuously through the remaining wizard screens until the setup is fully complete and saved.
(Optional) Repeat steps 2–5 for any other unused or duplicate projects sharing the same source/target domain pair.
Proceed to Archive the project.