To resolve:

  1. Use the fax cable that is included with your all-in-one printer.
    • Insert one end into the LINE IN or EXT OUT port.
    • If you experience difficulty inserting the fax cable, use a known "working" telephone cable (RJ-11).
    • Use the telephone cable that is connected to your telephone.
  2. Re-insert the telephone cable into the LINE IN or EXT OUT port of the printer.
  3. Connect the other end of the telephone cable to the wall jack, or DSL filter, or ATA depending upon your phone service.
  4. Inspect the LINE IN and EXT OUT ports for damage.