How to Install a New Email Client in Internet Explorerby Jacqui Lane
When you click on an email link in Internet Explorer, the browser is designed to automatically launch your default email client. In Windows, the default program is usually Outlook Express if you are using Windows XP or older, or Windows Live Mail if you are using Windows Vista or 7. If you want Internet Explorer to launch a different mail client, you can change your default client in the browser's Internet Options menu.
Launch Internet Explorer.
Click on the "Tools" menu and select "Internet Options."
Click on the "Programs" tab.
Click the button that says "Set Programs." Select "Set Your Default Programs" from the window that appears.
Select your email client from the list of programs on the left side of the screen and click the button that says "Choose defaults for this program."
Check the box next to "Mailto" and click "Save." Internet Explorer will now launch your preferred mail client when you click on an email link.