Celemony has updated Melodyne to version 4.2.3.
Melodyne version 4.2.2 has an error which, in certain constellations, when the application starts, displays a "version is expired" message and quits again. 4.2.3 fixes this problem. Documents saved with the 4.2.2 version are not affected by the problem in any way. After installing the new version you can continue working as always.
You can find the installer in your user account.
For additional guidance, inspiration, a search function and films, visit the Melodyne Help Center