Using Multiple SAP Assistant Windows 
Use
With each SAP Assistant window you can work with a single R/3 system/client pair. Even when
working with a local repository, you can only work with one system at a time.Opening another SAP Assistant window allows you to work with multiple systems or local repositories simultaneously.
Procedure
Choose the New Browser Window button or choose File à New Window.
Result
A new SAP Assistant window opens, allowing you to log into a different system or local repository. When the new window opens, you are not logged into the system or local repository with which you are working in the previous window.