Engage Comm Error Diagnostics

Includes directions for terminal models: P400, e235, e280, e285, P200, P400, V200c, V240m, V400c, V400m, m400, m424, m440

Use this when basic Comm Error troubleshooting hasn't resolved the issue and you need deeper hardware or network configuration diagnostics.

Common causes for communication errors include hardware connection problems and network settings that need adjusting.

Resolve the issue

1

Check the hardware

Check the peripheral connections at the back of the device. If your setup allows, ensure each cable is securely plugged in; reconnect or secure anything loose.

• If a peripheral is broken, get its part number (P/N) and replace it — contact your Merchant Services Provider, Level 1 Helpdesk, or Verifone Helpdesk.

Confirm the power outlet is functional; switch to a known-working outlet to test.

If your site setup permits, move the device — without its cables — to a known-working station to isolate the issue.

• If the issue follows the device, the device itself may need replacement.
• If the issue does not follow the device, one of the peripheral cables is the cause — isolate further to find which one.

✅ Issue fixed — stop here. ❌ Still not working — continue to the next step.

2

Check the network configuration

Verify the device's current network configuration:

• Account setup: get the correct values from your Level 1 Helpdesk, Merchant Services Provider, or Verifone Helpdesk, if applicable.
• DHCP: automatically assigns IP addresses and other settings (subnet mask, gateway, DNS servers) to devices.
• Static: provides a fixed IP address and configuration, commonly used for added security.

If any of these are set incorrectly, they need to be adjusted to resolve the Comm Error.

Only use the network details provided by your network manager. Incorrect details can prevent successful device pairing and transactions.

✅ Issue fixed — stop here. ❌ Still incorrect — use the update guide below.

Update the network configuration

Choose the method that matches your device's interface.

System Mode

1

Open system mode

Press 1, 5, and 9 simultaneously. A sub-menu appears — press 1, 5, and 9 together again. Select Supervisor, then enter the device password (default 1668321, unless changed).

If the default password doesn't work, contact your Merchant Services Provider, Level 1 Helpdesk, or Verifone Helpdesk for the password.

2

Navigate to Ethernet settings

Press the green (o) button to open the system mode menu. Select Administration → Communications → Ethernet → eth0.

• If eth0 isn't available, check the peripheral cables, focusing on the Ethernet connection.

  • If it becomes available after reconnecting, continue to the next step.
  • If it's still not available, contact your Merchant Services Provider, Level 1 Helpdesk, or Verifone Helpdesk.

3

Adjust the network values

Select Ethernet, then view and adjust: IP Address, Subnet Mask, Gateway IP Address, DNS1, DNS2.

4

Save and reboot

Tap the arrow at the top left of the screen and select Yes to save. Then reboot by tapping the arrow at the top right until you reach the main menu and selecting Exit → Reboot, or hold the red (X) button.

Comm Control

1

Open Comm Control

Press 1, 5, and 9 simultaneously. Select Comm Control → More → Configuration, then enter the Comm Control password.

If the default password doesn't work, contact your Merchant Services Provider, Level 1 Helpdesk, or Verifone Helpdesk for the password.

2

Open the network interface settings

Select Network Interface → Ethernet or LAN → Configuration → IPv4. Select DHCP, then select No.

3

Adjust the network values

View and adjust: IP Address, Subnet Mask, Gateway IP Address, DNS1, DNS2.

4

Save and apply

Press the red (X) button or tap the top-left arrow to go back. Select Save → OK → Yes to apply. Once the device shows "Accepted," select OK.

5

Reboot

Tap the top-left arrow, select Exit → Yes, then hold the red (X) button or select Reboot to power-cycle the device.

To learn more about accessing a device's settings to view its current setup, see Device Settings.

Keywords

Also called: engage diagnostics, comm error deep troubleshooting, network config update. Search terms: comm error diagnostics, system mode, comm control.