Lexmark MX510
For Windows users
From the document that you are trying to fax, open the Print dialog.
Select the printer, and then click Properties, Preferences, Options, or Setup.
Click Fax > Enable fax, and then enter the recipient fax number or numbers.
If necessary, configure other fax settings.
Apply the changes, and then send the fax job.
Notes:
For Macintosh users
With a document open, choose File > Print.
Select the printer.
Enter the recipient fax number, and then configure other fax settings, if necessary.
Send the fax job.