To do this task
Log in to QuickBooks as the QuickBooks administrator.
If you're not logged in as the administrator, reopen the company file and
enter the administrator's user name and password.
If you forgot the administrator's name, enter ADMIN in the User Name field.
Go to the Company menu, click Set up Users and Passwords, and then click Set up Users.
If prompted, enter your password again.
In the User List window, select the administrator's name. Click Edit
Enter the new administrator's name.
Change the password.
Enter a challenge question and answer.
Click Next and then click Finish.
Setting up the QuickBooks Administrator