What is TrIDLib.dll? This standard Win32 DLL library, based on TrID's core engine, make adding file identification / file recognition capabilities to any kind of application a very easy & quick process. If you need a managed library, check the TrIDEngine. For more Info Go to Author website http://mark0.net/index-e.html Functions in the UDF are: _TrIDLib_Startup _TrIDLib_Shutdown _TrIDLib_GetInfo _TrIDLib_GetRealExtension _TrIDLib_GetVersion _TrIDLib_GetFileTypeDef Here is main udf