Hi Ming -
It looks like your data source is pointing at "localhost" vs. an actual machine name. What happens if you use the real name of the machine, or the machine's actual IP address (vs. 127.0.0.1)?
My data source is always pointing to the actual name of the machine. I never use localhost.
FYI, this error happen after I upgrade my Tableau Server from 7.0.1 to 7.0.9.
When I get the error, I have tried to republish the workbook and run the extract refresh. For the first time extract refresh after the workbook republishing, everything is working fine. Extract refresh is successful and I can open the workbook. However, when I refresh the extract for the second time, the error above shown and the workbook cannot be opened.
Then, I tried to republish the workbook again, and the scenario above keep repeating.
Any idea why the error happen and how to solve it?
Really appreciate your help and feedback. Thank you.