To Select a Seed File

From the ribbon, choose File > New.
The New dialog opens.
Click the Browse button adjacent to the Seed field.
The Select Seed File dialog opens. The default filter is "MicroStation DGN Files [*.dgn]."

Select Seed File dialog
(Optional) To list all files, or AutoCAD files in the list box, choose "All Files [*.*]" or "AutoCAD Drawing Files [*.dwg]" from the Files of type option menu.
(Optional) To select a different source disk drive or directory, choose the desired drive or directory from the Look In option menu.
Do one of the following:

In the list box, select the desired seed file.

or
In the File name field, key in the name of the desired seed file.
Click Open.