It's always a good idea to change your password on a regular basis, making sure to add a level of complexity.
In Outlook.com, in the upper right corner, right-click your profile picture, and then click Account settings.
Note: If you're prompted, log in to your Account page. This prompt may occur in a different browser window than the one where Outlook.com is loaded.
Under Basics, click Change password.
Note: As a security measure, you might be prompted to prove your identity. If so, decide how you want to receive the security code — by phone or email — and then click Send code. When you receive the code, enter it and move to step 3.
Enter your current password, enter your new password, reenter your new password, and then click Save.