> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bead.run/llms.txt
> Use this file to discover all available pages before exploring further.

# Sandbox connection troubleshooting

> Work through sandbox connection troubleshooting for application forwarding, preview links, desktop access, and reconnects.

For sandbox connection troubleshooting, inspect the machine before changing forwarding or retrying work:

```bash theme={null}
bead inspect MACHINE_ID
```

Wait for readiness. If a persistent machine is paused, check available credit and resume it through its lifecycle controls. See [Pause and resume](https://docs.bead.run/snapshots/pause-resume.md).

## An application URL refuses access

Machine application URLs require authentication. A hostname alone does not grant access. Use the CLI's authenticated localhost forwarding:

```bash theme={null}
bead open MACHINE_ID --port 3000
```

For an explicit local port:

```bash theme={null}
bead port-forward MACHINE_ID --port 3000 --local-port 3001
```

Keep forwarding running and use the printed localhost URL. Check that the application is listening on the requested port inside the guest. See [Forward ports](https://docs.bead.run/connect/ports.md).

## A preview link stopped working

Worktree preview access ends at expiry, revocation, pause, or machine deletion. The service must be running on the bound application port. Existing streams close within the current authorization window; reconnect the browser after restoring access.

Create or revoke preview links through [Share a dev preview](https://docs.bead.run/worktrees/sharing.md). Keep fragment tokens private.

## Desktop access fails

A desktop grant has its own scope and lifetime. An application preview does not grant desktop access. Create a fresh authorized watch or invitation link through [Watch and human takeover](https://docs.bead.run/agents/watch-takeover.md) and check the current machine state.

## A connection drops after pause or restore

External TCP peers may disconnect across pause. Applications and long-lived WebSockets must reconnect. Recover an uncertain command by its execution ID before deciding whether to run it again.

## Machines cannot reach each other

Private networking reachability depends on placement. Inspect the returned network information rather than assuming every machine pair can communicate. See [Private machine networking](https://docs.bead.run/parallel/networking.md).

For broader outages, read [Service status](https://docs.bead.run/help/status.md).


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