1. Log into the Office 365 portal (http://portal.office.com).
2. Click Work or school account.
3. From the Home Page of Office 365, click on the Settings Icon (the gear)
4. In the settings sidebar, click the Password option.
5. On the Change Password page, enter your old password followed by your new password twice to change the password, then click Submit.
Please be sure to follow our password policy when creating a new password. :