This is how you should write the e-mail you are going to send as a fax to a fax number:·TO = DestinationFaxNumber@efax.ipfone.comFor Example: 7866105861@efax.ipfone.com (just the 10 digit, no dashes or spaces). To fax multiple numbers, send them with comma's in the email to address with the same format.·SUBJECT = Anything you want, it will be included on the first page of the PDF document sent as fax (Cover sheet).·BODY = Anything you want, it will also be included on the first page of the PDF document sent as fax (Cover sheet).In the body of the email you have to set it as plain text (No HTML).These are the file extension you can attach to the e-mail: TIFF, JPEG, PDF & DOC, DOCX .It is recommended that you write some text on the body of the e-mail besides the file attached to avoid delivery issues.