Cannot Send or Receive Even Though a Connection has been Correctly Established

Make sure that the PC-FAX driver have been installed on the computer. The PC-FAX driver is installed with FAX Utility. Follow the steps below to check if it is installed.

Select System Preferences from the Apple menu > Printers & Scanners (or Print & Scan, Print & Fax), and then make sure the printer (fax) is displayed. The printer (fax) is displayed as "FAX XXXX (USB)" or "FAX XXXX (IP)". If the printer (fax) is not displayed, click [+] and then register the printer (fax).

Select System Preferences from the Apple menu > Printers & Scanners (or Print & Scan, Print & Fax), and then double-click the printer (fax). If the printer is paused, click Resume (or Resume Printer).

Set the user name and password in the printer driver. When the security feature that restricts users from accessing the printer's fax function is enabled, and a fax is sent from the computer, user authentication is performed with the user name and password set in the printer driver.

Try the resolutions for fax connection and fax settings.