Issue Accessing CRM Organization Service from WCF service hosted in IIS

Consider the following deployment scenario:

 

 

 

 

In such a scenario you may get an exception while calling organization.svc. In that case one solution
is to check the AppPool (Application Pool) of your Website in IIS in which the WCF service is hosted.
The AppPool should be CRMAppPool for your WCF service, this should solve the problem.