Solution Throws Unable to find an embedded skin with the name 'Metro'

Solution Throws Unable to find an embedded skin with the name 'Metro'


Problem: 


When using different Assembly Versions of the Telerik.Web.Ui.dll in the Global Assembly Cache, the following or similiar error throws in the logs:


Telerik.Web.UI.RadFormDecorator with ID='RadFormDecorator1' was unable to find an embedded skin with the name 'Metro'. Please, make sure that the skin name is spelled correctly and that you have added a reference to the Telerik.Web.UI.Skins.dll assembly in your project. If you want to use a custom skin, set EnableEmbeddedSkins=false.


The used versions are Version 2013.2.611.45 by CalendarSummary WebPart and the Version 2015.1.225.45 used by Collaboration Manager.

 

Solution:


Manipulate the web.config of all needed webapplications and servers in the farm to redirect the old assembly to the new one:

​

<dependentAssembly>

   <assemblyIdentity name="Telerik.Web.UI" publicKeyToken="121fae78165ba3d4" />

   <bindingRedirect oldVersion="1.0.0.0-2015.1.225.45" newVersion="2015.1.225.45" />

</dependentAssembly>

 

https://msdn.microsoft.com/de-de/library/0ash1ksb(v=vs.110).aspx

 

Run an IISRESET /NOFORCE and the problem should be gone!