Process Explorer is a tool that is very helpful in assuring you have all the correct DLLs. It is distributed freely by Microsoft at http://www.microsoft.com/technet/sysinternals/utilities/ProcessExplorer.mspx. This application will show you all files that your application has loaded while it is running, and the path where each DLL is loaded. It is a good idea to use your application to see if any others are loaded.