In a vi text editor as reached from the command line shell with vi filename.txt or an excellent GUI such as MacVim, enter:

:%s/\r/\r/g

and your file will be beautiful, even if only parts of it were messed up with ^M non-working line breaks.

Thanks to the comment at this post.

The below is the why that goes with this how: Style content in Drupal using standard HTML tags (and have it match your custom site perfectly and meet your styling needs!)

Gus: