Unrecognized tag prefix or device filter msg error

Question

Hi 

I am just creating a logout page using referance application(code) just created as it is, also referring referance also but still error at msg:popmsg.

 

Register

 <%@ Register TagPrefix="cc" Namespace="AMR.Components.ErrorHandler" Assembly="ErrorHanWebCustomCtrl" %> 

 

<msg:popmsg id="PopMsg" runat="server" /> 

 

in Design mode error

"Control con`t displayed its tagprefix is not registerd in the webForm"

 

can some one help me how to get rid out.