VSTO: SecurityException Request for OraclePermission failed

Question

We wrote a MS Word Add-In using VSTO 2.0. In this Add-in we've connected to a sql server database. Anything went fine. Now, our client wants to switch to an Oracle DB. When we try to connect now via the Sytem.Data.OracleClient Provider, we get a SecurityException saying:

"Request for the permission of type 'System.Data.OracleClient.OraclePermission, System.Data.OracleClient, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed."

during the call of connection.open

Our Assembly has full trust. The DataAccess Layer Assembly is loaded via Unity. All Assemblies are strong named

Any Ideas?

Google gave me just some ASP.NET related stuff.

Answer 1

Problem was, that the main Add-In had full trust, but the dal assembly didn't