A short note on Apple’s Latest upgrade, El Capitan. I still use my original Magic Jack for calls to the U.S..
When I upgraded to OS X El Capitan, my Magic Jack stopped working. I still had one Apple MacMini that I had not upgraded and I hooked it up today and the Magic Jack works.
If you depend on the original Magic Jack and you use an Apple desktop, then the latest upgrade will kill Magic Jack.
You have been warned