When I run my application i got this I see in my console this message \"Unknown class FirstViewController in Interface Builder file.\"
I am running TabBar applicati
This happened to me just after Git merge and resolving few conflicts.
It had screwed up my XCode project.
I tried all over the StackOverflow. At first I thought my Custom class .m file hasn't been added to the Compile Sources class list. But it's one case, however even after adding it, it gave me same issue back.
How I resolved:
.xib file and its backing custom class .m and .h files.Cheers!