Visual Studio 2008 - 在运行时卡住，在我尝试调试时说“无法中断执行”

I'm running a C# program on Visual Studio 2008 It freezes at some point, and when I try to pause for debugging, VS2008 freezes also. when I close the program console window it pops up a "unable to break execution" message box. When could be the cause of this?I'm running a C# program on Visual Studio 2008