To work as Multicompany in Payroll-Admin, you must have user name and password created for you by the administrator. And that login must have ROLE_MULTICOMPANY is set.
When you login as a Multicompany for the first time, you go to options and click on users and change your password.
To login as Multicompany follow the below steps
Go to PayrollAdmin login page , enter the User name
Enter the Password
Click on Login
If user name and password matches with the user record created by admin, you will be able to successfully log in to SchoolAdmin Lite. If user name and password is wrong, you will get a error message saying Invalid Username or password. You need to re type correct user name and password to login.