I have a C# windows application written using VS .NET 2005. In my application I am referencing a COM dll that has a procedure named SendToDDC. When my code calls this procedure, I am getting an unhandled SecurityException 'Permission denied'. I call this procedure mulitple times in my code. The first call always works successfully, but any subsequent calls receive the exception. I do not need to know how to handle the exception, but I would like to know what I need to do to avoid it. I need to call this procedure or my application is useless.