If you have an old ''Gramps XML '' database generated '''4 years ago''', then you could have some difficulties to import them into last stable release ('''3.1.x'''). '''Gramps-1 ''' did not store '''[[Events_in_GRAMPS|EVENTevent]] ''' as primary object and did not use bsddb references. There was some limitations (''size, informations, encoding''), '''new Gramps versions ''' tried to fix them.