840.01CS431dw

Lexmark CS431dw 840.01 Error: Network Connection Guide

Error 840.01 on the Lexmark CS431dw indicates that the network interface is encountering communication timeouts. This error is common in environments where IP addresses are assigned dynamically but might conflict with other devices. Restoring stable network communication is essential for enterprise printing workflows.

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Common causes

  • 1Local IP address conflicts on your network.
  • 2Intermittent wireless signal or interference.
  • 3Incorrect subnet mask or gateway configuration.

Solutions

IP Address Verification

  1. Print the network settings report via the printer menu.
  2. Check if the printer has a valid static or dynamic IP address.
  3. Ensure the gateway address matches your router's IP.

Refresh Network Settings

  1. Navigate to Settings > Network/Ports > TCP/IP.
  2. Choose to reset the TCP/IP stack.
  3. Re-enter Wi-Fi credentials or check the Ethernet cable connection.

Steps to follow

  1. 1

    Check Settings

    Print the network info page to verify current connectivity status.

  2. 2

    Configure IP

    Manually set an IP address to prevent lease conflicts.

  3. 3

    Test Connection

    Verify connection by pinging the printer IP from a networked PC.

Frequently asked questions

It is a network-level communication error, usually triggered by IP conflicts or connectivity timeouts.

Yes, assigning a static IP address in your printer's settings often prevents these intermittent connection errors.

You can view the IP address on the printer's display panel under the Network settings menu.

Lexmark CS431dw 840.01 Error: Network Connection Guide | Vimazdev