Hi Kenny, can you get us a screenshot of the following so that we can get a better error message possibly?
1. Go to Tableau Server.
2. Click on Server > Status.
3. Click on Background Tasks for Extracts.
4. Locate the failed extract refresh in the top viz (it has a little red x).
5. Hover your mouse over it and then take a screenshot of the tooltip that appears.
That should give us a better message than those alerts.