Get question mark instead property name and value in Debug Mode in Visual Studio

My issue is: during Debug Mode in Visual Studio I can not see property name and it value. Any suggestions? UPD This bug/feature is reproducible in college PC.

UPD(15.06.2012)

The base class is placed to separated lib. Base class is abstract. And... Two times Debug was working fine, after making changes in source file (in screen-shots) and then running the project.

Please notice that Immediate window can not evaluate this expression.

MailProcessingViewModelContext inherits that base class that I have mentioned in the top of UPD.

It's a bug in Visual Studio that's caused when you scroll through the properties list with a mouse. Click the down arrow at the bottom of the menu instead.

As somebody on top already mentioned, you need the debugging symbol files (.pdb's) for every dll that you are using which is not your code, otherwise VS can't look 'inside'.

and if it's obfuscated you won't see anything at all

This would happen if you were debugging an ASP.NET wizard and wanted to check a collection of something, all elements in the collection that are in the current wizard step (current context) would be visible while the others are there but not in context just now hence marked as questionmarks -> ?

Maybe it could be something like that in your case. I guess it could be the same scenario

For me, this happened when I had a getter property in a class model pointing to itself. It was a copy paste error, notice the property name is ShouldNotProcess, and in the getter it's returning itself. The return was supposed to be: return !this.ShouldProcess;

public bool ShouldNotProcess
{
    get { return !this.ShouldNotProcess; }
}