Error: The WebSocket handshake failed: cPanel Server operation timed out (polkit.service)

December 05, 2025 04:20
Updated

Symptoms

When accessing the Terminal emulator from within a cPanel account or WHM, you receive the error:

Error: The WebSocket handshake failed at 0:00:00 AM.

Description

Problems with the Policy Kit (polkit) service may cause the required authorizations to time out and prevent opening a Terminal session. If the polkit service is not running, restarting it and the systemd-login service should restore the service to the Terminal emulator.

Workaround

Access your server using SSH as the root user. You will need to use an external SSH client rather than the Terminal emulator in cPanel or WHM.
Verify the status of the polkit service:
```
systemctl status polkit.service
```
If the service is not active, restart it:
```
systemctl restart polkit.service
```
Restart the systemd-login service as well:
```
systemctl restart systemd-logind
```

Additional Information

Other reasons for this error message are covered in the following articles:

Terminal WebSocket handshake failed error (via service subdomains)

Terminal returns a websocket error when Imunify360 is running.