Fax is adding blank pages between documents

The fax is adding a blank page between each page of the fax transmission. What could be causing this?

The sending fax machine could be set to scan double sided, but the document is only single sided

A fax machine set to scan double sided will insert blank pages between the pages of a single sided document.

Explanation: Scanners set to double sided are looking for information on both sides of the page. If the double sided selection is

Resolution 1: Set the sending fax machine scanner to single sided.

Resolution 2: Print to both sides of the document that is to be fax by the sending fax machine.

Resolution 3: Throw away extra blank pages.