I have Vista, VS.Net 2008 and RS4 installed. When I debug an application F10 does not let me step into a method. But if I use the .Net IDE step into button, it does. What I'm not sure is if it is a problem with the way I've configured .Net or if it's a problem with something in RS4. I guess I'll blame RS4 first as I know I'll get an answer from someone far quicker if I try to blame Microsoft! Whatever the outcome, I'd appreciate it if someone could tell me what I might have misconfigured or perhaps need to do.