
You can use the Lock option to lock new file references when you create them, or use it to lock existing file references.
To lock or unlock an existing file reference from the Outliner
-click either the reference node or referenced objects you want to lock or unlock.
In the Outliner, locked references are indicated by an
icon.
To lock or unlock an existing file reference from the Reference Editor
-click the reference and select Reference > Lock Reference or Unlock Reference from the menu that appears.
In the Reference Editor, a lock
icon beside the reference indicates that it is locked.
To lock a file reference when the reference is created
.
-click in an open area and select Reference > Create Reference >
.