How to authorize only some of the controls like text field,knob in my VI?

[culstar44]

I am using it to avoid unnecessary problems created by the user in my GUI and my block diagram. 

I want a password to overwrite some the controls from their initial value. Other controls are set by the user.

I am using LabVIEW 2010.

[JarleEkanger]

You could use the event structure ("event loop") for this. 

For any control that you want to protect, you'd create a value change case. Within this case, implement e.g. a pop-up subVI that prompts for a password and returns if the user typed in the correct password. If password is OK, perform the value change or action related to a button pushed, and if password is not OK, do nothing.