When you try to upgrade a file, the Add-On Data Conflict message displays.
Schema conflicts experienced when upgrading may be occurring in two possible scenarios:
The file you're upgrading contains a schema. Another model opened in your current session contains a schema with an identical ID to the schema used in the file you are upgrading. When both files are opened in the same Revit session, only one schema will be maintained, leading to the removal of the other.
These steps will resolve the issue if you have encountered the error in the first scenario. If you continue to experience the errors continue troubleshooting with scenario 2.
The file you're upgrading contains a schema, and one or more loaded families in this file also contain a schema with the same ID. When a 2023 or older file is upgraded to Revit 2024.3 or later, or a Revit 202 4file is opened in Revit 2024.3 or later, only one of the conflicting schemas will be maintained, the other will be removed.
Contact the add-on vendor for additional information about the consequences of removing this schema.