I have 2 quick suggestions...they may help or they may not, and seeing as how I primarily work on a PC and Access db's and rarely with Excel sheets this might fall in the latter category. I would try 2 approaches (both I saw in the Tableau 8.2 Roadshow): 1. When importing try to import using the "legacy" mode. Click on the arrow next to Open "Open with Legacy Connection". 2. Have you downloaded the Tableau Plug In for excel? I have found quite a few neat tricks especially with aggregation and reshaping directly in Excel before you ever import into Tableau.
Again I am not sure if this will help but they were 2 things I have had some luck with in the past. Hope you find your answer
Thanks Christopher! May be a Mac thing but it doesn't look like I have the legacy mode. Also I believe that the plugin is packaged with the Excel plugin for Mac (the below link seems to confirm this).
I double checked to make sure there were no filters or aggregates on the extract. Everything seems to be fine on my end. It may be time to reach out to their helpdesk.
It's not much fun, but your best bet will probably be to chase through the Logs at the time the refresh / error occurs, to see which field it is choking on.
It may something as simple as a letter in a numerical field, or some other dirt, that is throwing it off, or it may be one of your Calculations.
The logs should help point to the specific trouble spot.
I assume you're already upgraded to 8.2.3 on your Mac?
By the way, you might have better luck posting problem questions like these into the Forums that are not associated with our local Tableau User Group forum. Although we locals would love to help you out, you'd get many more eyes on your problem, and thus, responses, posting out in the wider Community.