The type 'test_class' is defined in an assembly that is not referenced. You must add a reference to assembly 'App_Code, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'.

what is this, how can i resolve it 

Looks like there is a problem in reference.where is this test_class located ? is it in your project or is it in an external dll?

Hi,

Could you please tell us how you get this error message?

We might get such issue when we deploy the website on server where there is not needed assembly. If so, you can copy the assembly to server. For more information, see http://www.xheo.com/xdn/kb/article/10003.aspx.

If you try to unit test the class exists in App_Code, please refer to http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=3028857&SiteID=1.

If this doesn’t help you, please feel free to let me know.

I hope this helps.