Notifying that all properties have changed on a ViewModel
In case you're reading this in 2016, you can use ObservableObject and notify that all of the properties have changed by doing:
RaisePropertyChanged(string.Empty);
Unfortunately this is not possible with the current code-base of MVVMLight
In the short term your have 2 options:
User your own custom base class. And by custom base class I mean "Do not inherit from the MVVMLight class".
Download and compile MVVMLight in Release mode. This will force the "VerifyPropertyName" method to be excluded. Of course then you don't get the value of property name checks.
I am sure Laurent Bugnion will have this fixed soon.