Error "A potentially unsafe URL has been blocked" Or "TypeError: e.get_blockType is not a function" Opening File With URL Action

Published: 07 Apr 2015
Last Modified Date: 01 Jul 2020


When using a URL action to open an external file, after the File protocol has been allowlisted, one of the following errors might occur:
Unexpected Error
An unexpected error occurred. If you continue to receive this error please contact your Tableau Server Administrator.

uncaught exception: [object Object]
TypeError: e.get_blockType is not a function​


A potentially unsafe URL has been blocked


  • Tableau Server
  • Chrome
  • Firefox


Firefox and Chrome do not allow access to external files using the File protocol. The URL action might work in Internet Explorer.


Newer versions of Chrome and Firefox do not allow for local file access from an external web-request. The browsers will not cross from the http protocol to the file protocol.

For security reasons, browsers will not launch some file types, such as .jar or .exe files, resulting in the "Unsafe URL has been blocked" error.
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