Question : WCF service error when trying to connect to SQL Request for the permission of type 'System.Data.SqlClient.Sql<wbr />ClientPerm<wbr />ission, System.Data

I have a WCF service running locally on a Vista computer which needs to communicate with SQL 2008 runing on a dedicated server.
When the application is complete the WCF service will run on a dedicated web server.

When the service goes to open the SQL Connection
A SecuirtyException is raised with this message
Request for the permission of type 'System.Data.SqlClient.SqlClientPermission, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

Answer : WCF service error when trying to connect to SQL Request for the permission of type 'System.Data.SqlClient.Sql<wbr />ClientPerm<wbr />ission, System.Data

SQL server secuiry is not the problem,   Runing in joint mode.

Proble resolved.   CAS issue.   Assembley was being run from shared Network drive.  Move to local drive and not having problem anymore.