Resolve Umbrella Warn Page Returning a 404 "Page Not Found" Error

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Updated:October 29, 2025
Document ID:225322

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    Introduction

    This document describes how to resolve the "404: Page not found" error in the Cisco Umbrella Warn page.

    Prerequisites

    Requirements

    There are no specific requirements for this document.

    Components Used

    The information in this document is based on Cisco Umbrella.

    The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, ensure that you understand the potential impact of any command.

    Problem

    The Umbrella Warn page is returning a "404: Page not found" error.

    Solution

    Check to see if you have added the Umbrella IP ranges from this article to the external domains list: Secure Web Gateway's IP List and Domains to Allow in Customer Firewall. If they have been added, remove them from the external domains list and try the warn page again. If problems persists, please contact Umbrella Support.

    Revision History

    Revision Publish Date Comments
    1.0
    29-Oct-2025
    Initial Release
    TAC Authored

    Contributed by Cisco Engineers

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