How to change the default Notebook stylesheet

Amir: 2 days ago

For everyday work I use a custom notebook template. Its name DefaultModified.nb However, in order to open it I need to first open a built-in default notebook, go to the Menu/Format/StyleSheet and define the style that I need.

My question: Is it possible to fix in Mma a style of the notebook that will open by default? In my case the DefaultModified.nb.

Note that I do not want to kill or change the Default.nb style. Let it be in case that something goes wrong. I only want to ask Mma to open another template by default.

Muhammad: 2 days ago

Wolfram has an article discussing precisely this: