Unable to Append Data To Extract From a .csv File

Published: 07 Mar 2017
Last Modified Date: 22 Mar 2018


When attempting to append data to an extract from a .csv file in Tableau Desktop 10.2, the following error might occur: 
"Internal Error - An Unexpected error occur ed and the operation could not be completed"


  • Tableau Desktop 10.2.0
  • Windows 7 Enterprise
  • Text Files


Option 1

Upgrade to Tableau Desktop 10.3 or 10.2.8. For more information, see Upgrading Tableau Desktop.

Option 2

Try one of the following alternative workarounds: 
  • Add the CSV as a second connection and use Append Data from Data Source instead of Append Data from File.
  • Perform a wildcard union in a single data connection, and then create the extract. See Union Wildcard Search for more information. 
  • Build a manual union using the following steps:
  1. Connect to the primary file
  2. Select Extract
  3. Connect to the file with the data you want to add.
  4. Drag the second  file out to create a new union.
  5. keep the default 'specific (manual)' union option.
  6. Update both files 
  7. Refresh the extract to update with the new rows.


This behavior is related to known issues (ID: 625052 and 653064) that has been fixed in a later version of Tableau Desktop. 
Did this article resolve the issue?