I'm a new user of Tableau Public. I am using it in Parallels (Version 14.1.3 (45485)) with Windows 10 (Version 1803, OS Build 17134.706).
I downloaded the latest version of Tableau Public and created a profile.
I tried to open/import an Excel file from my own library and also tried to use one of the Tableau files but with no success. I uninstalled and reinstalled Tableau but I still get the same message: -
An error occurred while communicating with Tableau Data Extract.
Bad Connection: Tableau could not connect to the data source.
Error Code: 3834846E
There was problem and the data engine could not start properly.
While I see some threads related to this general problem, I don't see anything related to this specifically.
This KB seems similar to your question, please have a try at the resolution provided in it.
Error "Bad Connection: Tableau could not connect to the data source" When Opening a Second Tableau Desktop Instance
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