Get your taxes done using TurboTax

If I have bought software that says I can use it on 5 different computers and the software box says it can be used on Windows AND Mac, then please explain why I can only use it one operating system. Your end user agreement doesn’t state anything about only using the software on one operating system. Why do I need to purchase a second software when I can use one software for 5 computers and your software box says it can be used on Windows and Mac?