When Outlook (or most email clients) install they like to set themselves to be the default email program. You just need to change it back:

1. Open the Control Panel (Start > Control Panel).
2. Open Add or Remove Programs.
3. Click on Set Program Access and Defaults.
4. Click on the double-arrows next to Customer to expand the section.
5. Under Choose a default e-mail program, select the program you would like to use.

This will change the default email program in both the Start menu and in Internet Explorer.

-SW