There are instances when you need to edit the email of your users.
Note: You can only edit the email address of individuals who have not verified their email.
Assuming the above applies, you can navigate to the Users -> Manage Users and click on a specific account you would like to edit.
A user with a verified email address who needs to update or change their email can navigate to their Account page via the drop down menu under their name when logged in on the right-hand side -- select Account, midway down the page you have the option to add additional emails. Once that additional email is verified it can be made the primary email on the account and the other email can then be removed.