Actually when we want make copy of cad with all external file to another folder or computer. the file will not found location saved path. to avoid this do eTransmit.

The Create Transmittal dialog box is displayed.
If you enter -ETRANSMIT at the Command prompt, options are displayed.
When you select a set of drawing files in a transmittal package, it automatically includes all related dependent files such as xrefs and font files. you can also bind multiple xrefs in multiple drawings by using Etransmit

bind multiple