The “Cast” feature in Microsoft Edge utilizes the Media Router API (derived from the Chromium engine) to actively scan your local network for compatible receiver devices, such as Google Chromecasts, Android TVs, or Miracast-enabled displays. While this is a highly convenient feature for home users wanting to project a YouTube video or a browser tab to their living room TV, it is a significant security and bandwidth liability in an enterprise environment. It generates unnecessary multicast traffic (mDNS/SSDP) across corporate VLANs, and more dangerously, allows users to accidentally project sensitive web applications or proprietary data to unsecured displays in conference rooms or public areas.
This guide explains how to completely disable the Cast (Media Router) feature system-wide in Microsoft Edge using Group Policy, preventing local network discovery and unauthorized screen sharing.
Disable Cast (Media Routing) via Group Policy
To enforce a strict block that disables the underlying API and removes the Cast option from the browser’s context menus, we must deploy an administrative template. Note that this requires Windows 11 Pro, Enterprise, or Education editions.
- Log into Windows 11 with an Administrator account.
- Press the Windows Key + R to open the Run dialogue box.
- Type
gpedit.mscand press Enter to launch the Local Group Policy Editor. - In the left-hand navigation pane, navigate precisely to this path:
Computer Configuration > Administrative Templates > Microsoft Edge - In the right-hand pane, locate the policy named Enable Cast.
- Double-click the policy to open its configuration window.
- Select the radio button next to Disabled.
- Click Apply, then click OK.
Verify the Security Lockdown
Group Policy changes require the browser to read the registry upon its next launch. Close all active instances of Microsoft Edge.
To verify the restriction is active, reopen Microsoft Edge and click the three horizontal dots (Settings and more) in the top right corner. Scroll down to “More tools”; the “Cast media to device” option will be completely absent from the menu. Additionally, if you right-click on an active webpage or an embedded HTML5 video player, any “Cast” options will be missing from the context menu. The browser is now permanently sandboxed from discovering or communicating with local media receivers on your network.