Error "Unable to connect to the data source" Or "User(s) do not have permission to access datasource" Accessing Published Workbooks

Option 1

As the site administrator or data source owner, grant the affected user the 'Connect' permission for the published data source. See Data access for published Tableau data sources for more details.

Option 2

Republish the workbook using Embedded password for the published data source(s).

1. Open the affected published workbook in Tableau Desktop. See Open a published workbook from the server for steps. 
2. Republish the workbook and ensure the Authentication setting for all published data sources are set to Embedded password. See Set Credentials for Accessing Your Published Data for more information. 

Option 3

Re-save the workbook using web authoring and embed credentials. 

1. As the workbook author or site administrator, edit the workbook using web authoring. See Edit Tableau Views on the Web for steps.
2. Select File, and Save As.... 
3. Give the workbook the same name as the existing workbook to overwrite it, and select the Embed password for data source box. 
4. Select Save.

Option 4

Check the database to confirm the user has permission to the underlying database and is not being blocked or denied access on the database side. Consult your Database Administrator for more information.