Hidden Item Settings under Folder Options getting changed everytim

Hi All,

I am using Windows Xp SP2. From past few days, three settings under
Tools-Folder Options - View are getting changed everytime I restart my
computer. The settings are 1)Do not show hidden files and folders, 2) Hide
Extensions for Known File Types and 3)Hide protected operating system
files(Recommended).
By default these three should be selected or checked, but everytime I start
my computer i.e., after shutdown, I see these settings getting unchecked or
unselected. Can anybody guide me how to fix these?

Help would be really appreciated.