Here are the steps you need to follow:
1: Launch the Services on your computer.

2: Search BI Connector Service and right-click to Stop the service.

3: After stopping the service, go to the path "C:/ProgramData/Guidanz/BI Connector/sessions", and select and delete all.

4. Go to the path "C:\ProgramData\Guidanz\BI Connector\cache", and select and delete all.

5: Start the BI Connector service after deleting the sessions and cache.

6. Now try Test Connection in the BI Connector Config window and Save the DSN.