Thanks virtualasset for your reply , but as JohnWilson said: "All anyone has to do is turn off "Mark as Final".
Yes.. It's that easy!
And also: "Adding a modify password gives some protection but it is easy to break".
Yes I know that to.
The amazing thing is I searched for a days (up and down left and right) but i didn't find any thing even paid!!
OK.. I'll search again maybe...