Why does Word freeze when I'm debugging?

Question

Whenever I'm at a break point in a certain C#.NET application in Visual Studio 2008 and I fire up Microsoft Word 2007, word will fail to open until I restart the C# application. I have a few theories about why, but does anyone know for sure?

Answer 1

This can be because Word is sending out DDE messages to top level windows, and your app is not able to process it since it is hung in the debugger. Raymond Chen has a blog post on this (though not directly related to debugger, but same effect).