NetPoint schedules are not guaranteed to be backwards-compatible. That is, for example, a file created in a more recent release of NetPoint will not necessarily be able to be opened in an older release of NetPoint. Schedules created in NetPoint 4 and above will never open in NetPoint v3.0, as they have different file extensions.
All schedules created in NetPoint 4 and above are given an .np4 extension. All schedules created in versions prior to NetPoint 4 are given a .npt extension. Versions 4 and above can read both .np4 and .npt schedules; however, NetPoint v3.0 cannot read .np4 files. If an attempt is made to open an older NetPoint file (.npt), it will be converted all the same to a project folder. The original .npt file will continue to exist as a backup.