No document in that direction
What happened
You clicked a tool in a toolbar to see the next or previous document in a view when you had already followed a link to a document that's not the next or previous document.
Note: You may also have chosen View > Switch Form when there was no alternate form available in the application.
What you can do
To see the next or previous document, return to the view and open a document from it before using the next or previous document tools.
If you have Designer access, you can create different forms with which to display documents.