WCF.. /serviceActivations could not be found

Question

Error:

The type 'AAA.BBB', provided as the Service attribute value in the ServiceHost directive, or provided in the configuration element system.serviceModel/serviceHostingEnvironment/serviceActivations could not be found.

 

I get this error while browsing the webservice hosted locally. I tried various ways from google, unfortunately doesn't work.

 

Technical details : iis 7, pool - asp .net 4.0

                                 visual studio 2012, .net framework 4.0 

 

 

Looking forward with simple steps to resolve error.