The Agile Add-in has been installed and integrated with CA PPM but the project synchronization with the Agile Central gives a "API-1029 authentication error" error message.
Check on errors in the Agile Product Sync job log and the bg-ca.log:
Related possible solutions are:
1) Under Administration - Project Management - Settings: Fill in the Agile Integration Owner.
2) Assign "API - Access" global right to the user who runs the Agile Product Sync job.