COMM-ERR-99DL7400 Pro

Fujitsu DL7400 Pro COMM-ERR-99: Communication Fix

The COMM-ERR-99 code indicates a loss of communication between the printer and the host PC. It happens when data packets are interrupted or port configurations mismatch between the device and the driver. The solution usually lies in checking physical cabling and Windows port settings.

1 views

Common causes

  • 1Faulty data cable: signal degradation in internal wires.
  • 2Incorrect driver configuration: assigned port does not exist.
  • 3Electromagnetic interference: network cables near unshielded data lines.
  • 4Windows spooler conflicts: print queue frozen.

Solutions

Diagnóstico rápido

The device appears as 'Offline' in the print queue. First, verify if the USB or parallel cable is securely connected and if the printer has been restarted.

Solución paso a paso

  1. Check connection: Swap the data cable with a known-working one to rule out hardware failure.
  2. Verify Windows port: Ensure the driver points to the correct port (e.g., USB00x).
  3. Serial settings: If using a serial port, confirm baud rate and parity match the printer settings.
  4. Reinstall driver: Remove the printer from the queue and re-add it via Control Panel.

Prevención y mantenimiento

Avoid data cables longer than 3 meters to prevent EMI. Keep drivers updated and avoid disconnecting data cables during active jobs.

Cuándo llamar a un técnico

If the error persists after testing on another computer, the mainboard's communication port might be faulty.

Ficha técnica del equipo

  • Technology: Impact dot matrix
  • Speed/throughput: High data transfer rate
  • Connectivity: USB 2.0, Parallel, Ethernet option
  • Feeding capacity: Heavy-duty continuous paper
  • Compatible consumable: Series DL7400 ribbon (D30L-9001-0895)
  • Recommended use: Corporate multi-user environments
  • Drivers / official firmware

Steps to follow

  1. 1

    Cable Check

    Disconnect and re-connect the interface cable at both ends.

  2. 2

    Spooler Clean-up

    Stop the 'Print Spooler' service and clear temp files.

  3. 3

    Port Selection

    Ensure in printer properties that the selected port is active.

  4. 4

    Test Print

    Send a test page using the Fujitsu utility.

Frequently asked questions

It is a connectivity error, so it doesn't physically damage the equipment, but it halts all production operations.

No, the ribbon is mechanical and has no electronic parts that would influence data transfer.

Yes, but ensure your driver settings match the specific COM port emulation of the adapter.

Use shielded data cables and avoid using cheap USB hubs for industrial printer connections.