Comparison of Windows fax printer options

Starting with version 0.5.2 the setup of YajHFC has three options for creating a fax printer. This article tries to give a short comparison to help you decide which one to choose.

Mode of operation

  • Redmon:
    Uses Redmon to create a virtual printer port. Redmon then launches YajHFC when a document is printed to this virtual printer port.
    Because Redmon will run as part of the Windows spooler service (which runs as the SYSTEM user), it has to switch the user id to launch YajHFC, which may lead to problems because the run environment will not be exactly the same as when YajHFC is started by the user directly.
    Also, on a terminal server, YajHFC will always be started on the console, not the session the user is logged in on.
  • RedmonEE:
    Uses RedmonEE to create a virtual printer port. RedmonEE then launches YajHFC when a document is printed to this virtual printer port.
    Usually this works better than Redmon, especially in Terminal Server environments. Unfortunately RedmonEE is beta software and 32bit only (and 64bit support not planned according to the authors).
  • mfilemon:
    Uses mfilemon to create a virtual printer port. YajHFC creates a named pipe on start. mfilemon then launches a small batch script that writes the printed data to that pipe.
    Usually this works most reliably (and probably most secure), especially in "complex" enviroments like Terminal Servers, because no user process has to be launched from the print spooler.
    The disadvantage, however, is that YajHFC must be running (e.g. be in Autostart) for the fax printer to work.

Please note that I personally can only test against default installations of the "normal" workstation versions of Windows XP/Vista/7 (YajHFC being a Open Source project I do not have the resources to do more here...).
(Terminal) Server versions should usually work, too, but I need your feedback if problems arise with such a Windows version.

Comparison table

64bit Terminal Server RemoteApp YajHFC must be running
Redmon yes no partially no
RedmonEE no yes partially no
mfilemon yes yes yes yes



Usually the default the setup program chooses should be fine for most users.
If you are experiencing problems with one of the Redmon options (such as "session 0 isolation" popups) it is usually worth giving the mfilemon method a try (please let me know if this is the case, so future versions may be improved).