Thanks for your advice, but I want to do is to prohibit the user to choose, now i have an object, but I do not want the user to modify it manually, but only by loading the program to modify
I agree with Kerry.
Since AutoCAD has so many ways to manipulate objects it makes it tough to lock anything up.
A couple of strategies that I've used are:
1. If the environment is contained (in-house project) you can work with the CAD department to explain the benefits of using your program to modify the objects. Then set a company policy.
2. Create tools that modify the object that are better, easier, smarter than the AutoCAD tools. This way you entice the user to use your program rather than force them.
Both of these strategies leave many technical holes for users to work around.
You could try plugging those holes as they are discovered. You might get to 80% and for some environments that may be enough.