After I googled for this error for some time, without any luck, I decided t o write a quick blog post about it, just to help others which might have the error due to the same reasons as me.
Today I got this error “XAML Namespace http://schemas.microsoft.com/expression/blend/2008 is not resolved.” in a Silverlight 4 project. I happened right after I added some VisualStates in Blend 4. I could remove the VisualState XAML and everything would then build again fine. As meantioned I googled the error but couldn’t find a solution.
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