When debugging an ASP.NET on my new machine, I ran into the following weird situation: I started debugging a web application for which I had set some breakpoint in the global.asax.cs file, somewhere in the Application_Start handler.

Now that's about as early in the application you can set a breakpoint, but I had some configuration issues I was debugging. The strange thing was, the breakpoint was never hit by the debugger, ever...

Then I noticed that, contrary to what I was used to, Visual Studio did not show "(Running)" in its title bar... This was an indication the debugger had not attached itself to the development webserver properly. After some googling around I came accross the following site which solved the issue. Apparantly VS gets confused when IE8 is installed... strange.

This registry fix solved the problem!