The problem I am having is that I am getting a System.IO.FileLoadException when trying to load the RWLock.dll on a test box and Windows xp machines. This is the exception that is thrown when it tries to load the dll on the windows 2003 server machine (most likely 32 bit): System.IO.FileLoadException: A procedure imported by 'rwlock, Version=1.0.3889.27926, Culture=neutral, PublicKeyToken=null' could not be loaded. File name: 'rwlock, Version=1.0.3889.27926, Culture=neutral, PublicKeyToken=null' --- System.Runtime.InteropServices.COMException (0x8007007F): The specified procedure could not be found. (Exception from HRESULT: 0x8007007F)... However, we have not had any problems trying to run this on a Windows 2007 server machine (64 bit). Any ideas? Thanks in advance :)