Hyperlink .SubAddress - How to interpret it
Thanks to Shyam Pillai for this information:
Hyperlinks in PowerPoint may have both an .Address and a .SubAddress property.
In general, the Address identifies the document the link points to, while the .SubAddress identifies a location within that document.
Not all links will have a .SubAddress. Links may have a .SubAddress and no .Address (ie, when the link is to a slide within the current PowerPoint file).
.SubAddress takes the following form:
.SubAddress=SlideID, SlideIndex, SlideTitle
You can use commas with blanks .
e.g 256,, or ,2, or ,,NEXT or ,,This is a title are valid entries.
The priority of lookup is left to right.
The SlideID is looked up first. If it exists, the show moves to that slide; otherwise, the Slide Index is looked up and then the last Title field.
The text contained in the title field is compared against the titles of the slide, this search is case sensitive. You can create specific links to slides with titles - "My Title" , "MY TITLE". Since the search is case sensitive, if the exact title is not found the hyperlink fails.
Since PowerPoint uses commas to separate fields in the .SubAddress, commas in the Title will usually cause the link to fail and create other problems. It's best to avoid them.
The title field can contain some keywords also like NEXT, FIRST etc. These keywords get priority over slide titles i.e if the the third slide has a title - NEXT and the address of the shape on the first slide reads ,,NEXT , when clicked it will move to the 2nd slide and not the 3rd.
You may also see a .Subaddress like:
-1,1, Slide Title
This indicates a link to an external PPT file, slide 1, with title "Slide Title"
In other cases, there could be a .Subaddress like:
Several hyperlinks in the same presentation might also have "hyperlink" in place of the actual slide title. This seems to be PowerPoint's way of noting that the titles are identical so should not be used as a way of uniquely identifying the slide.