Set default text - Unable To Open File

[Artman]

Fairly new to Textmaker but trying to set up Default Text on my wife's PC which I have done successfully on my own. So I go Character>set the typeface and size>set as default>choose change for all new documents etc. and then get a pop up window saying Unable To Open File. After this I close down and it has not saved my changes. I can't figure out what I am doing wrong? Help appreciated.

[SuperTech]

Please share a screenshot of the error for better understanding.