If you load or render a scene with XRefs, but the originally specified path of the XRef object or scene can’t be found, or if the XRef object name doesn’t match the object name in the source file, an alert appears telling you this.
This alert works in the same way as the missing bitmap dialog, and provides you with two options.
Lets you open the file. The referenced scene will have placeholders, but will not exist in the scene.
Displays the Configure XRefs Paths dialog which you can use to specify the correct file path. This lets you modify, delete, add, and change the list position of the paths 3ds Max uses to look for missing files.
This panel is similar to the one displayed by choosing Customize Configure User Paths XRefs.
If this problem occurs during network rendering, the dialog doesn’t appear, but the errors are written to the network log file.