Good Morning,
if you are using the Face to DXF ICMech tool, install this latest delivered version:
www.ironcad.it/download/ICMechanical/ICMechanical_25.11.08_X64.exe
Furthermore, dropping the tool with Right button mouse, you will have the settings about this tool:
(These are the same settings in IPROSettings.exe)
Please control if the red boxed option is set. When this option is uncheked,
the threated holes are not exported to DXF.
I hope this can help you
M