What is "Files Replacing Policy"?

[afzaldir]

I am editing Sysdm.cpl file in system32 folder. But when I edit this file correctly. After Reboot Windows XP it will come back its original state. But If I use software to change my startup logo it will never change in future. Why??? How can I permanently make changes manually, not using software?

[patio]

System files aren't meant to be edited and doing so can render a machine un-bootable...
From what i'm aware what you are trying to accomplish can only be done with a third party eye candy program...