C# – Could not load file or assembly > ‘System.Windows, Version=2.0.5.0

csilverlight-4.0

On first load of my Silverlight application I keep getting this error:

Could not load file or assembly
'System.Windows, Version=2.0.5.0,
Culture=neutral,
PublicKeyToken=7cec85d7bea7798e' or
one of its dependencies. The system
cannot find the file specified

but by just refreshing the page, it'll be solved!

it seems that it's known bug of Silverlight :
http://connect.microsoft.com/VisualStudio/feedback/details/464190/silverlight-compilation-problem-in-team-build-environment

they suggest workaround, but does not work in my case.

Best Answer

Well actually 'System.Windows' assembly is copied to the output directory solved the problem form me. Just make sure that it is copied to whereever you're going to be executing your app, not just the Debug folder. Also there is a very good alternative that doesn't have similar problems: SilverUnit