Problem connecting Samsung phone to windows XP system

I could not be able to successfully connect my Samsung phone to the Windows XP system through Samsung’s PC studio and I could add ringtones in my phone. I have migrated to Windows 7 and installed the latest version of Samsung’s PC studio. I have also installed phone drivers. But it is not able to connect to the PC studio. What is to be done to connect to the PC studio? If anybody knows the solution to solving this, please help me. I will be thankful for all your help.
