My Visual Studio (2008) Editor has stopped to underline Errors (this nifty wavy red lines). I can't really tell when, but it can be related to the installation of .Net Framework 3.5 SP 1 or the MVC Beta (which I guess is unlikely). Furthermore have I installed and uninstalled both CodeRush and Resharper for evaluation purposes (decided not to keep either one of them).
Does anyone know the problem and how to restore this functionality again?
Have you checked Tools→Options...→Text Editor→C#→Advanced→Underline errors in the editor?
I usually like to reset my settings after messing around with plugins, as they tend to mess with settings: Tools→Import and Export Settings...→Reset all settings.