If you cannot send or receive faxes, try these solutions:
Windows: Make sure the product appears in Devices and Printers, Printer, or Printers and Other Hardware. If the product does not appear, uninstall and re-install the FAX Utility.
Mac: Select System Preferences > Printers & Scanners (or Print & Scan or Print & Fax) and make sure your product appears. If your product does not appear, click + and add your product. If the product does appear, double-click it and make sure it is not paused.
If your phone line includes voice mail answering services, calls or faxes may be inadvertently received by your voice mail service.