I'm developing a web part in SharePoint 2013 using VS2012. In this web part I'm trying to use third party dll controls like telerik but i face a problem :

Could not load file or assembly......

and the file .ascx.g.cs will be empty when add register line as bellow :

<%@ Register Tagprefix="telerik" Namespace="Telerik.Web.UI" Assembly="Telerik.Web.UI" %>

I try to add dlls to gac and also try to add dlls to package but didn't fix my problem any suggestions??

2 Answers 2


You'll need the full four part assembly name, with the Assembly, Version, Culture and PublicKey, to reference an assembly in the GAC.


yes its work with James Answer and to be more clear I wrote it as :

<%@ Register Tagprefix="telerik" Namespace="Telerik.Web.UI" Assembly="Telerik.Web.UI, Version=2011.3.1115.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4" %>

For my case thanks

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.