NetPoint schedules are not guaranteed to be backwards-compatible. For example, a filed created in a newer release of NetPoint 4 will not necessarily open in an older release of NetPoint 4. Schedules created in NetPoint 4 will never open in NetPoint v3.0 as they have different file extensions.
Opening Legacy Files
All schedules created in NetPoint 4 are given an .np4 extension. All schedules created in versions prior to NetPoint 4 are given a .npt extension. NetPoint 4 can read both .np4 and .npt schedules; however, NetPoint v3.0 cannot read .np4 files.
When opening a file in NetPoint 4, only .np4 files are shown by default. If an attempt is made to open an older NetPoint file (.npt), it is copied to a new file with the same name but with an .np4 extension. The original .npt file will continue to exist, but it is the new .np4 file that will be opened and inherit any changes made during planning.