A different Jahia Module with the same Id already exists 

Question

After some refactoring, I'm not able to deploy my module. On the Jahia log, I can see the following message:

ERROR [http-nio-80-exec-30] org.jahia.osgi.BundleUtils: A different Jahia Module with the Id module-test already exists 

Answer

This message means that an existing bundle with same ID (artifact name) is deployed.

First, check that you are trying to deploy a new version of your bundle (and not a complete other bundle that has nothing to do with the current one except the name)

Actual bundle module-test in your current version uses a certain group ID, and the new version of your bundle may use another group ID.

If so, you simply need to remove the actual version from the Jahia Administration (you may have to disable this bundle from several sites, keep the associated content), then install your new bundle (and re-enable it to your sites). It should be fine!