When upgrading to TX DWA 15.12.4 the upgrade should be done through the Web Service.
The reason for this is a missing statement in the upgrade scripts provided by the installer.
If you cannot access the Web Service you need to apply the following statement to your project repository database:
SET [PrimaryDataFieldId] = NULL
WHERE LEN([FixedValue]) > 1
AND [PrimaryDataFieldId] IS NOT NULL
How to apply the script:
Ensure that you have a fresh backup of the project repository database before proceeding.
1. Open SQL Management Studio
2. Connect to the Sql Server where the project repository is located.
3. Right click your project repository in the Object Explorer and select New Query
4. Paste the above sql statement into the query window and press F5.