To Copy Line Style Definitions from One Line Style Library to Another

Open the Line Style Editor dialog ( Drawing > Home > Attributes > Line Style > Manage ).
From the File menu, choose Open.
The Open Line Style Library dialog opens. (You can also use File > New to create a new line style library.)
In the File list box, select the file you want to be the line style library.
Click Open.
The Line Style Editor dialog displays relevant information on the line styles contained in the selected line style library.

Once you have a line style library file assigned, you can then select then the source and destination files.
From the Line Style Editor's File menu, choose Manage.
The Manage Line Style Definitions dialog opens listing the line styles in the current line style library.
From the File menu, choose Open Source File.
The Select Source Line Style Library dialog opens.
In the File list box, select the name of the file that you want to be the source file (the file from which you want to copy line styles), and click Open.
The filename and list box on the left of the Manage Line Style Definitions dialog contain the source entries; and the filename and list box on the right contain the destination entries. You can copy line styles from the source file into the destination file, rename the line styles in this file, and delete line style resources from this file. The resource file is open only for reading and copying line styles into another file; the original resource file is not modified by copying styles from it.
Select the name of the line style definition you want to copy in the source list box.
Do one of the following:

Click Copy.

or
Drag the line style name over to the Destination list box.

The line style name appears at the bottom of the Destination line style name list.
Click OK.
Note: You can copy line styles from more than one source file in the destination file at one time by using File > Open Source File.

Note: You may also open more than one destination file to add styles as well, by using File > Open Destination File. If you have made changes to the current destination file, you will be prompted to save them before continuing.