If you need to delete or deactivate a user you'll need to:
- Sign in to Microsoft Office 365 using your Office 365 Admin details.
This would have initially been set up as email@example.com with its associated password.
- On the Office 365 Admin center bar, on the left hand side of the screen, click on "Users" and then "Active Users".
- Select the user you want to delete.
- Click on "Delete" that appears on the left hand side of the screen.