Modules on the environment do not match with modules in the package

If you try to deploy an 8.0 to 8.1 upgrade to sandbox/UAT where modules have been renamed, you will get the error "Modules on the environment do not match with modules in the package" together with a list of missing modules.

The regular process of renaming a module is to create a new module with the new name, move the code, delete the old module and add the old module name to the ModuleToRemove.txt files for removal during deployment.

When deploying the 8.0 to 8.1 upgrade to sandbox/UAT, Microsoft checks that the package holds at least the same modules as already deployed. But the ModuleToRemove.txt file is not taken into consideration during this check, and thus the modules appears to be missing.

The workaround is to keep and deploy empty models with the old names. Any code must of course be in the new models.

You can uninstall the empty modules at your next regular deployment using the normal process with the ModuleToRemove.txt file.

This is only an issue with 8.0 to 8.1. Not with, for example, 7.3 to 8.1.