Unable to show hidden files & folders in XP

Symptom : In Windows Explorer --> Tools -- > Folder Option --> View, the "Do Not Shows Hidden Files & Folders" selection always been selected even you changed in to "Show Hidden Files & Folders"

Causes : This might be caused by virus infection.

Solution :

1) click on the start button --> run --> type : regedit

2) Explore the registry : HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL

you will see a value name called "CheckedValue" at the right panel. Double click the CheckedValue icon, and change the Value Data from 0 to 1.

3) Yes, you can then now try again to change the folder option in the Window Explorer.