Issue

The following error appears when trying to deploy an updated package from a development environment to a test environment.

"An item with the same key has already been added"

Symptoms

The issue was caused by an existing form on the Test environment.

Troubleshooting Steps

To resolve the issue the existing form on the target environment was deleted.

Afterwards, a new package was created from the development environment. With the new package created it was deployed on the Test environment successfully.