or download this
Deleting a key
WARNING: The following code will delete all information about the curr
+ent user's tip preferences. Actually executing this command would pro
+bably cause the user to see the Welcome screen the next time they log
+ in and may cause more serious problems. This statement is shown as a
+n example only and should not be used when experimenting.
...
$tips= delete $Registry->{"CUser/Software/Microsoft/Windows/" .
"CurrentVersion/Explorer/Tips/"};