If a user has to leave the organization, Admin can delete the user. Please keep in mind, deleting a user will completely delete all the user's data including the user name which cannot be retrieved anymore.
- Login to Zoho Docs http://www.zoho.com/docs.
- Click on the settings icon at the top-right corner near your user name.
- From the drop down menu click on Setup.
- In the popped up new window, Click on 'Users' tab and click 'User List'.
- Select the user whom you want to delete.
- Click on the 'Delete' button above the user details.
- A pop screen appears, enter the admin password.
- Click 'OK' to delete the selected user.