# Defining the Fax Printer > [HTML Version](definingthefaxprinter.htm) The fax printer is defined more or less just like any other A-Shell printer (i.e. via a printer ini file in the SYS: directory) with the following two mandatory requirements: DEVICE = FAX: PASSTHROUGH = OFF The identifies the particular fax server to use, and can be one of the following: • A local fax printer name (as it appears in the printer folder.) • A network printer UNC name, such as "\\\\servername\\printername". • NULL (nothing following the prefix FAX:) to specify the default local fax printer. Some examples: DEVICE = FAX:fax DEVICE = FAX:\\\\mainserver\\fax1 DEVICE = FAX: Note that the prefix FAX: must be used in all cases. This is how the A-Shell print spooling routine realizes that you want to use the A-Shell/FAX interface, which requires that it do some preliminary setup work (loading the winfax.dll, dynamically linking the functions needed, allocating temporary memory, pre-scanning the print file to extract the essential header commands, etc.) before doing the normal print processing of the file.