So I’m using 4.7.6 version. When I add map I downloaded from internet : http://tf3dm.com/3d-model/architecture-house01-81348.html , I get this : House01 has degenerate tangent bases which will result in incorrect shading.Can someone tell me how I could fix it? I’m a beginner so please use the shortest and easiest way to explaine it. Sorry for bad English 
Hi,
I am facing the same problem right now. Did you try to solve this problem? Please let me know. Thanks!!