Tools - Settings - Programs -
Tab External viewers

Under "Tools → Settings → Programs" in the tab "External viewers", the user may define programs (external viewers) for showing files, depending on their file extension. These are in addition to what is defined on the "Viewers" tab for FreeCommander's internal viewers.

Assignment of filters and programs (external viewers)

Different file extensions (in the column "filter") may be assigned to different external viewers (in the column "programs").

In the above example, the external viewer "i_view32.exe" is assigned for all file types.

You can define the same extensions for internal and external viewers. All those defined for internal viewers can be seen with "F3", and all those defined for external viewers can be seen with "Shift+F3".

Calling the external viewers

On activation of the menu item "File → View external" or the hotkey "Shift+F3", the listed filters are analyzed sequentially from the top down. The highlighted file is opened by the external viewer assigned to the first matching filter. Only checked rows are taken into account when matching a filter.


If FreeCommander is started from a USB stick, it is best if tools like external viewers use relative paths for the tool's start drive and start folder. This is because the USB stick could be a different drive on different PCs, and therefore folders with tools may not be found. Using relative paths ensures that the correct start drive and start folder will be found, no matter where FreeCommander is started from.

input:                                  %FcSrcPath%\..\UniversalViewer\Viewer.exe        [note: "\.." means "one level up"]
install folder:                          c:\tools\FreeCommanderXE
resulting configuration folder:  c:\tools\UniversalViewer\Viewer.exe

Editing the list of programs and their filters

The following buttons and shortcuts are available for editing the list of external viewer programs:

  • (Insert):        add new row
  • (F2):        edit the filter in the highlighted row
  • (Ctrl+Del):        delete the highlighted row
  • (Ctrl+):        move the highlighted row up
  • (Ctrl+):        move the highlighted row down

The input box "program" specifies the program which should perform the action for the highlighted row.

The input box "parameter" specifies any parameters required for the program in the highlighted row.