Xcode“ - [UIViewController _loadViewFromNibNamed：bundle：]加载了笔尖，但未设置视图插座。”错误

I'm using Xcode 4 and when I run my app, the first screen doesn't load. It fails in the simulators and on a device. I've searched for answers and they all say to make sure I've dragged the circles in Files Owner to the correct views. Sorry I don't remember the names of the things, I'm new to Xcode. I've dragged the circles to the correct view and tried many things but none of them worked. What could I be doing wrong?I'm using Xcode 4 and when I run my app, the fi