Tableau extract not refreshing when using WDC data source

Issue

Tableau Server is unable to refresh extract from Web Data Connector data source.

Environment

Tableau Server
Web Data Connector

Resolution

Verify that the Web Data Connector (WDC) has been whitelisted with the tabadmin command:
- https://onlinehelp.tableau.com/current/server/en-us/tabadmin_cmd.htm#whitelist_wdc
- Any external links the WDC points to must be on the secondary whitelist. This includes links to the Tableau WDC API library, jQuery etc:
  - https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js
  - https://connectors.tableau.com/libs/tableauwdc-2.1.latest.js
Verify that the Tableau Server computer can connect to the WDC, and any external links the WDC point to.
- Install Tableau Desktop on the Tableau Server machine.
- Connect to the WDC from Tableau Desktop and click Update now to pull in data.
- In case of connection issues or very slow connection, run a Fiddler trace to troubleshoot.
If using wildcards, and the above two options do not work, change the syntax of the wildcard value from "*" to "(.)*" (no quotation marks)

Cause

The Web Data Connector has not been whitelisted; or else the Tableau Server computer cannot connect to the API server linked to by the Web Data Connector.