When you sign up for a Hotmail account, you are asked to provide an alternate email address. Although this step is not required, it does help you regain access to your Hotmail account if you forget your password and the answer to your security question. Once you have created your Hotmail account, you can add an alternate email address by updating your profile. This also allows you to easily share information between your various email accounts. If you want to view which email addresses are linked to your Hotmail account, you can do this via the Account Information page.

How to Find the Other Email Addresses Linked to a Hotmail Account - 10