A few days back, one of my friend told me that he was having trouble with his Windows XP. The show hidden files and folders was not working at all. If he selected the radio button “Show hidden files and folders”, and then press Ok .. the changes would just disappear upon opening the dialog again. It was probably some virus attack after which the Windows registry was not being updated properly. So here is what I did to restore it back. Remember, apply all these steps at your own risk this site will not bear any responsibility for any inconvenience.
Procedure 1:

* Go to registry editor ( Start >> Run >> "regedit" )
* Navigate to HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Explorer \ Advanced
* In the right hand area, double click hidden and change the value to 1.
* Check it in your tools menu if the changes have taken effect.Procedure 2:

* Go to registry editor ( Start >> Run >> "regedit" )
* Navigate to HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Explorer \ Advanced \ Folder \ Hidden \ SHOWALL
* Look at the “CheckedValue” key… This should be a DWORD key. If it isn’t, delete the key.
* Create a new key called “CheckedValue” as a DWORD (hexadecimal) with a value of 1.
* The “Show hidden files & folders” check box should now work normally.For more information just subscribe in the email.