Hello, i recently purchased the book pcmag windows xp speed solutions. interesting book but im having some problems. the book tells how to change the way the prefetch folder acts by editing the registry. i follow the instructions exactly and reboot and then go back into the registry and check the key i previously edited and its right back to its original setting, as if id made no change. in another example i follow the instructions to change application priority. i start the program i want to change, go to the processes tab of the task manger, right click the app i just started, chose "set priority" and then select "above normal". i close out of task manager and then go back in to see if the change took hold and its right back to were it was before i made the change. this is not the first time for the registry, i once made a edit to stop the pop up balloons in the notification area. same thing, the edit would revert to its original setting as soon as i closed out of the registry. is there some program in windows that protects setting so they cant be changed? there must be some explanation. My computer is a Toshiba laptop running winxp media center edition ver 2002, service pack 2 . any help appreciated. thanks, tom.