Hi guys,

I tried to downgrade nuPIckers from 1.5.3 to 1.4.1 but now my site is really messed up with the following YSOD error

Attempt by security transparent method 'ClientDependency.Core.Mvc.HtmlHelperExtensions.RequiresCss(System.Web.Mvc.HtmlHelper, System.String, System.String)' to access security critical type 'System.Web.Mvc.HtmlHelper' failed.

Assembly 'ClientDependency.Core.Mvc, Version=1.7.0.4, Culture=neutral, PublicKeyToken=null' is marked with the AllowPartiallyTrustedCallersAttribute, and uses the level 2 security transparency model.  Level 2 transparency causes all methods in AllowPartiallyTrustedCallers assemblies to become security transparent by default, which may be the cause of this exception.

What does this mean and what can i do about it?

best regards