Reference Tracker versions 1.x used a slightly different file format than the current version of Reference Tracker. However, the current version of Reference Tracker can fully read the older file format. When you open an v1.x document, Reference Tracker creates a new document in the new format, and imports all the data from the v1.x document. This document can now be saved in the new format. The original v1.x document is left unchanged so that it can still be read by the previous version of the application.