Public Folder as default

Hello ,

We are on 4.1 SP05. When launch pad is loaded by default "My Favorites" is selected. From preferences,  we have option to choose "public folder " as default. As part of admin , I need to set this option for all users to show "Public Folder" as default . How can I do it. Do we need to change any XML settings ? Thanks in advance

Regards,

S