Though Windows Mail is used as the default e‑mail program by web browsers and other programs that support sending e‑mail, you can choose a different e‑mail program as the default. If you decide you want to change the default e‑mail program back to Windows Mail, you can do so at any time.
Open Default Programs by clicking the Start button , and then clicking Default Programs.
Click Set your default programs.
Under Programs, click the e‑mail program you'd like to use, and then click Set this program as default.
The first time you start them, some e‑mail programs display a message asking you if you want to use that program as the default. If you choose to do so, this program will become your default e‑mail program, even if you've chosen a different program using Set your default programs earlier.