Windows Sandbox shows “The connection to the Windows Sandbox environment was disconnected. Do you want to reconnect?” immediately after launch

Question

I am experiencing an issue with Windows Sandbox on Windows 11.

When I try to start Windows Sandbox, it opens briefly and then immediately shows the message:

“The connection to the Windows Sandbox environment was disconnected. Do you want to reconnect?”

After this, the Sandbox does not function properly or closes.

I have already tried several troubleshooting steps, including:

• Enabling Windows Sandbox and all required Windows features (Hyper-V, Containers, Virtual Machine Platform)
• Verifying virtualization is enabled in BIOS/UEFI
• Running DISM /RestoreHealth and SFC /scannow
• Resetting network configuration (netcfg -d)
• Restarting related services (vmcompute, vmms, hns)
• Reinstalling Windows Sandbox feature
• Checking that Hyper-V virtual switch (Default Switch) exists

Despite this, the issue persists.

Other virtualization features seem to work, but Windows Sandbox still disconnects immediately after startup.

Has anyone experienced this issue or knows what could be causing the Sandbox VM to disconnect right after launch?

Answer 1

Check logs in Event Viewer if you can find related record there.