I have just installed rails 4.2 . I have found this tutorial for making a quick blog: https://www.reinteractive.net/posts/32-ruby-on-rails-3-2-blog-in-15-minutes-step-by-ste
I had exactly the same ExecJS::ProgramError on Windows. The only solution that really helped was provided by KeithP here: Rails-4, ExecJS::ProgramError in Pages#welcome, i.e.,