How to fix Error 775 on Windows 11

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Why This Error Happens

Error 775 (ERROR_NOT_CAPABLE) occurs when a process running inside a restricted AppContainer—such as a UWP app, a Microsoft Store app, or an app running in Windows Sandbox—attempts to call a Windows API or access a resource that requires a specific “capability” not declared in its manifest. This is a security boundary enforced by Windows 11’s app isolation model, meaning the OS is intentionally blocking the action rather than experiencing a bug. It commonly surfaces when apps try to use networking (sockets, named pipes), microphone/camera, or other protected resources without the corresponding capability token.

Step-by-Step Resolution Guide

  1. Identify the app or process triggering the error. Check Event Viewer (Win + X → Event Viewer → Windows Logs → Application) and filter for Event ID 775 to find the exact executable or package name.

  2. Check the app’s manifest capabilities (for UWP/packaged apps). If you have access to the source or package:

  • Open Package.appxmanifest in Visual Studio or a text editor.
  • Ensure required capabilities are declared under <Capabilities>, such as:
    xml
    <Capability Name="internetClient" />
    <Capability Name="privateNetworkClientServer" />
  • Rebuild and resubmit/reinstall the package.

  1. Review App Permissions in Windows Settings. Go to Settings → Privacy & Security and check the relevant category (Network, Microphone, Camera, File System, etc.). Toggle On access for the affected app under “Let apps access your [resource].”

  2. Reset the AppContainer token (if using Windows Sandbox or containerized apps). Run PowerShell as Administrator and reset the app’s package:

   Get-AppxPackage *AppName* | Reset-AppxPackage

This clears corrupted capability tokens tied to the container.

  1. Update or reinstall the application. If the app is from the Microsoft Store, go to Microsoft Store → Library → Get Updates. For sideloaded apps, ensure the AppxManifest matches the correct capability declarations for the OS build, then reinstall via Add-AppxPackage.

Alternative or Verification Steps

  • Verify the fix: Relaunch the app and reproduce the original action (network call, device access, etc.). Confirm no Error 775 appears in Event Viewer afterward.
  • Alternative workaround: If you don’t control the app’s manifest, try running the application outside its sandboxed context (e.g., as a standard desktop app instead of packaged/MSIX) or use Task Manager → Details tab to confirm it isn’t unexpectedly running under a restricted AppContainer token.