The Default File paths window displays the paths to the subdirectories where any items you create (Bullet Lists, Timelines, Screen captures, etc) are created in. These paths entries are set when you create a new case.
If you move a case by a method other than the Convert Network Case option, these entries may be incorrect. The paths entries should all follow the CaseItems directory from the location of the current database.
If these paths are incorrect, you may reset them to the correct default by clicking on the Reset button. This restores all paths to the "CaseItems\Item Type" subdirectory structure.