"Error: Couldn't connect to OAuth Server at localhost" or "Error Code: 84223ADA" for Data Sources Using OAuth

Published: 19 Mar 2021
Last Modified Date: 04 Aug 2022


Upon connecting to data sources that require OAuth authentication from where a proxy server is configured, the following errors can occur:
Error: Couldn't connect to OAuth Server at localhost

Authentication failed
Error Code: 84223ADA


  • Tableau Desktop 2020.3 and later
  • Tableau Prep Builder 2020.3 and later
  • Windows
  • Data sources that require OAuth authentication(Google BigQuery, Google Analytics, .etc)


Option 1

If using Google BigQuery, use your web browser to connect to Google BigQuery web console and confirm if the data sets can be accessed there.

If you are unable to connect Google BigQuery and access your data sets with a web browser, please ask your internal IT team to white list the URL links for Google BigQuery on firewall, proxy and/or antivirus. 

Option 2

Delete the environment variables HTTP_PROXY and HTTPS_PROXY

Option 3

Use a batch file like bellow to launch Tableau Desktop. (This will disable the environment variables for the proxy setting)

------ tab_exec.bat -------------------
@echo off


start "" "C:\Program Files\Tableau\Tableau 2020.4\bin\tableau.exe"

Option 4

Set an exception so that the proxy server will not be used for communicating with localhost via Internet Option in IE as described in the article below.
Tableau Fails To Connect to Amazon Athena through Proxy With Error Code 37CE01A3

Option 5

Add an environmental variable NO_PROXY to bypass a proxy server when accessing localhost.

  1. Click the search (magnifying glass) icon on the Windows menu.
  2. Enter sysdm.cpl to the text box and click the icon
  3. Open the Advanced tab and click Environmental Variables.
  4. In the system variables section, click New to add the following environmental variable.
    • Variable: NO_PROXY
    • Value:;localhost
  5. Click OK to close the window.


On Tableau Desktop connecting to data sources that require OAuth authentication, such as Google BigQuery, Google Analytics, .etc, uses an additional java process to connect to these data sources. This java process is responsible for connecting data sources that require OAuth authentication as well as communicating to Tableau Desktop using local port.

If there is a proxy server configured on the machine where Tableau Desktop is running, the java process will try to communicate with Tableau Desktop via proxy server and fails.
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