Oracle Database Discussions

I am trying to troubleshoot a problem I am having using extproc on a window 2008 server running the 11.2 release of the database. I am receiving error ora-28576 lost RPC connection to external prcoedure agent. What I am trying to determine is whether it is a extproc setup issue in the listener or tnsnames file or is my dll failing. These are the steps I have taken.

Before changing any listener or tnsnames entries I call my library thourhg pl/sql and receive error: Invlaid DLL path.

So I change the listerner to SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = E:\oracle\product\11.2.0\dbhome_1)
(PROGRAM = extproc)
(ENVS = "EXTPROC_DLLS=ANY")
)
(SID_DESC =
(SID_NAME = CLRExtProc)
(ORACLE_HOME = E:\oracle\product\11.2.0\dbhome_1)
(PROGRAM = extproc)
(ENVS = "EXTPROC_DLLS=ONLY:E:\oracle\product\11.2.0\dbhome_1\bin\oraclr11.dll")
)
)

LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = extproc))
(ADDRESS = (PROTOCOL = TCP)(HOST = s4064b2008sched)(PORT = 1550))
)
)

ADR_BASE_LISTENER = E:\oracle


and add to tnsnames:

EXTPROC_CONNECTION_DATA =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = extproc))
)
(CONNECT_DATA =
(SID = PLSExtProc)
(PRESENTATION = RO)
)
)

when I run I get the error: unable to load dll.

I then place my dll in the appropriate directory and then I receive the ora-28576 lost RPC connection to external prcoedure agent. So i cannot tell if it is a dll issue or a extproc setup issue?