If you are facing the same issue, please look at http://weblog.west-wind.com/posts/2013/Nov/21/Visual-Studio-2013-Could-not-evaluate-Expression-Debugger-Abnormality for details.
Here is the answer which solved for me:
I have set the flag “use managed compatibility mode” in Tools | Options | Debugger | General.
For details, take a look at the link as he explained it nicely as a story 🙂
Am happy it worked, otherwise I just had to load project in vs 2k12 just to debug it which is annoying.
EDIT on 12th June 2014
I have updated my dev environments with visual studio 2013 update 2 (http://www.microsoft.com/en-us/download/details.aspx?id=42666) (as per Maria’s suggestion below) and removed “using managed compatibility mode”. I will be testing my apps (ps cmdlets, gui, services) and update you in couple of weeks if the debugger is ok for me.
EDIT on 26th June 2014
I have tested my apps and luckily for me everything is working nicely :). Even the debugger is doing pretty good job with new async/await model. So, see if you can upgrade to ‘update 2’ – hopefully this works in your environment too?. Thanks to Maria and debugger’s team!
Regards.