Every Visio drawing, including a TaskMap, uses a "hyperlink base" as the anchor point for relative hyperlinks in the drawing. The hyperlink base may be explicit or implicit.
Explicit Hyperlink Base
The properties of every Visio drawing include a field called the Hyperlink Base that is blank by default. Entering text into this field creates an explicit hyperlink base that will be used to form a complete, fully qualified path for relative hyperlinks.
If all of the web page hyperlinks in your TaskMap are pages on the same web site, you can enter just the unique parts of each URL in the hyperlink dialog for each link and enter the base of the URL in the Hyperlink Base field.
If all of the document hyperlinks in your TaskMap point to files that are stored on a central file server, you can enter just the unique parts of each path in the hyperlink dialog and enter the common path to the server in the Hyperlink Base.
Note that it is not necessary to create an explicit hyperlink base to use relative links. Refer to Implicit Hyperlink Base below.
To create or edit the Hyperlink Base
Select File/Properties from the Visio main menu, which will open the dialog box shown below:
Click once in the box to the right of Hyperlink Base.
Enter the complete URL or document path from which all other pages are derived, e.g.,
NOTE: There is only one Hyperlink Base in a Visio document. Consequently you cannot have relative paths for both documents and web pages in the same TaskMap.
Implicit Hyperlink Base
If a document does not contain an explicit hyperlink base, i.e., if the document Hyperlink Base field is blank, Visio forms an implicit hyperlink base by comparing the locations of the hyperlink source (the TaskMap drawing) and the target of the hyperlink. There are two possible results:
If the hyperlink source and hyperlink target documents are on different drive letters or UNC paths
Visio ignores the hyperlink base and treats the hyperlink as an absolute link.
If the hyperlink source and hyperlink target documents are on the same drive letter or UNC path:
Visio creates a relative link by combining the common part of the drive letter path or UNC path with the unique portion stored as part of the hyperlink.