Last Updated: July 23, 2021


After the release of the new WebView based Room Finder, you may receive the following error: Server Error: 401 – Unauthorized: Access is denied due to invalid credentials.

Note: Room Finder is not currently designed to work in GCC-High or DoD tenants.


The Outlook team is investigating the issue and will updated this article when more information becomes available.

Try one of the following potential workarounds to resolve this issue:

  • Enable OWA protocols for the affected user(s)

  • Enable modern authentication (OAuth2.0) in Exchange

  • Enable Microsoft Exchange Add-In

  • Clear the WebView cache folder.

    1. You must close all Office applications before doing this step.

    2. Right click the Start button and select Run.

    3. Copy and paste either of the following locations into the Run box and press Enter.

      • %localappdata%\Microsoft\Office\16.0\Wef

      • %localappdata%\Microsoft\Outlook\

    4. Delete the webview2 folder.

    5. Repeat steps b through d using the location you did not use the first time.

  • Make edits to the registry using the steps listed here: How to revert the Outlook Desktop WebView based Room Finder to the legacy Room Finder

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