Unity crash - "Automatic import prefab disabled"

Time to time - especially while changing prefabs, importing or saving project - unity keeps crashing and after it starts again, it reports this message:

Automatic import for 'Assets/Game/City/_FBX_models/houses/_residential/neo_5fl_all_in_1.prefab' was disabled because the asset importer crashed on it last time. You can use 'Assets -> Reimport' to enable automatic importing again.

It usually disables this particular prefab, so we suspect it is corrupted somehow. Unfortunately, this prefab is used in our huge scene many times in a bunch of different modifications, so we'd rather get it fixed instead of creating brand new one. We don't wanna keep reimporting all the assets over and over again either. Does anyone have similar experience with prefabs corruption? Any suggestions how to fix it? thanks