GetPersistentManager problem? Can't save a scene anymore

Been getting this, what is it? I see this, and when I try to save a scene, it shows again, and additionally says it could not save the scene.

GetPersistentManager ().WriteFile (i->path, kBuildNoTargetPlatform, kDontReadObjectsFromDiskBeforeWriting)

close unity then run unity as administrator solved the problem for me! check also if the antivirus stopped unity