I'm trying to figure out an issue.  The Desktop application can connect to the data source, an Excel file on a SharePoint server.  The workbook publishes fine to the Tableau Server.  It's during the extract refresh that the error occurs.

Below is the error message from the Background Tasks report on the Server:

The Excel workbook does have a macro that executes upon the workbook opening.  If it matters, the macro simply sets the visibility of some sheets.  Here is a partial screen shot of the Excel worksheet that is the data source:

The name of the sheet is "Equipment List Tableau".  Every cell has a formula in it.  They all pretty much look similar to this one (cell range will vary):

=IF('Cab in White - Equipment List'!B11 <> "",'Cab in White - Equipment List'!B11,"-")

The Server does have Run As access to the SharePoint server and the server location is in the Authorized Forward Server List registry entry.

Suggestions as to why we're getting this error?  Things to check?