Recently while trying to delete a managed solution from one of our environments, we got the below error. Failed deleting solution MainManagedSolution. Solution dependencies exist, cannot uninstall. Click on View Dependencies. Click on See solution layers We can see Active Contacts has a dependency on the custom column, and it is part of an unmanaged layer … Continue reading "Failed deleting solution. Solution dependencies exist, cannot uninstall / Remove unmanaged layer– Dynamics 365 / Dataverse"