How to Set a Default Email in Windows 7
An email client such as Outlook 2010 allows you to instantly send and receive emails from linked email accounts. If you have multiple email clients installed on your computer, only one will be configured to work as the default email client. You must use the Default Programs option if you want to switch the default email client in Windows 7.
Click "Start" and then click the program labeled "Default Programs."
Click the option labeled "Set your default programs."
Click the email program that you want to set as the default program.
Click the option labeled "Set this program as default."
Click the button labeled "OK" to finish setting the selected email program as the default email program.