After considering the various problems that you might face by using Skype as the VOIP tool on your Mac, you might want to consider looking elsewhere for communication software. It’s a great tool for collaborative work and won’t cost you anything to use. You can easily set up a chat room with up to 15 participants.If the computer can support 10.11 or later, decide if you want to install the latest supported version for your computer. Go to Apple Support to check your computer's compatibility with the latest operating system.