Weird error

Suddenly everytime i click on play i get this error:

Why am i getting this error? Can someone help me on this? Is there a way to solve it? And most important, WHAT THE F*CK IS “BUILD SLAVE”?!

Edit: I solved the issue. But i still want to know why is there a hidden file in my drive that Unity installed and is called “Build Slave”

I figured out what was the problem. I was searching and i’ve discovered that almost everyone that had this issue made the same thing.

This “glitch” or something like that is an error that can occur when you import .FBX files to your project and try to change it in some way. My problem was that i was using a “force method” to do something via script and that kinda bugged the model, which made this error log me displayed.

The solution is basically REMOVE the asset .FBX completely from your project and reimporting it OR change the name. This most occur when importing a character that already comes with animations outside Asset Store.