Managing personal Outlook.com account settings, security, and privacy
You can use any voice phone, too. A land line will work and you can have Microsoft's system call you and tell you a code to use. You can also generate one you can print on a piece of paper and stick in your wallet if you want. If you don't have a second account, create one. What's so hard about that? Create one on a separate mail system, like Google or Yahoo so there's a path other than Microsoft to receive the code.