You can choose from three types of folder path information to save with an attached
reference: a full path, a relative path, and no path.

Specify a Full (Absolute) Path

A full path is a fully specified hierarchy of folders that locates the file reference.
A full path includes a local hard drive letter, a URL to a website, or a network server
drive letter.

Specify a Relative Path

Relative paths are partially specified folder paths that assume the current drive
letter or the folder of the host drawing. This is the most flexible option, and enables
you to move a set of drawings from your current drive to a different drive that uses
the same folder structure.

If the file that is being referenced is located on a different local hard drive or
on a network server, the relative path option is not available.

The conventions for specifying a relative folder path are as follows:

Specify No Path

When no path information is saved with the attached external reference, the following
search is initiated in the order shown:

• Current folder of the host drawing
• Project search paths defined on the Files tab in the Options dialog box and in the
  PROJECTNAME system variable
• Support search paths defined on the Files tab in the Options dialog box
• Start In folder specified in the Microsoft ^آ® Windows ^آ® application shortcut

Specifying the No Path option is useful when moving a set of drawings to a different
folder hierarchy or to an unknown folder hierarchy.

Know When a Referenced Drawing Has Been Relocated

If the drawing you are working on contains an xref that has been moved to a different
folder, a message is displayed at the site of the xref when you load the drawing.
The message indicates that the xref cannot be loaded using the old path. When you
specify the new path, the xref is reloaded into your drawing.

Use Project Names to Define Referenced Drawing Paths

Project names make it easier for you to manage xrefs when drawings are exchanged
between customers or if you have different drive mappings to the same location on
a server. The project name points to a section in the registry that can contain one
or more search paths for each project name defined.

If the program cannot find an xref at the location specified by the search path, the
prefix (if any) is stripped from the path. If the drawing has a PROJECTNAME value
set and a corresponding entry exists in the registry, the program searches for the
file along the project search paths. If the xref still is not located, the program
search path is searched again.

You can add, remove, or modify the project names that exist in the registry. The folder
search paths beneath the project name can also be added, removed, or modified.

The search paths beneath the project name can be added, removed, or modified in the
same manner as the project name. The order in which the folders are searched can also
be modified. Projects and their search paths can only be edited through the Files
tab in the Options dialog box. You cannot edit project names at the Command prompt.

Once you have established a project name and the search paths you want associated
with that project name, you can make that project name the currently active project.
The program searches the paths associated with that currently active project for xrefs
that were not found in the current folder of the host drawing, the full search path,
the current drawing folder, or the program support paths.

Change Reference Paths in Multiple Drawings (Advanced)

When you relocate drawing files or the external files that they reference, including
other drawing files, text fonts, images, and plot configurations, the reference paths
that are saved in the drawing need to be updated. The Autodesk Reference Manager lists
referenced files in selected drawings and provides tools to modify the saved reference
paths without having to open each drawing file. You can also use Reference Manager
to identify and fix unresolved references.

Reference Manager is a stand-alone application with its own Help system. To access
it, click Start menu (Windows) (All) Programs Autodesk AutoCAD Reference Manager. If you are working on a network, it may not have been installed
on your computer.