Unable to load DLL 'opencv_core242': The specified module could not be found. Emgu CV


I'm trying to start using emgu CV open CV for C#. But I'm having trouble making it work. I'm following this guide to make simple program using emgu CV Link but I get following error: (any idea what I'm doing wrong?)

    System.TypeInitializationException was unhandled
      Message=The type initializer for 'Emgu.CV.CvInvoke' threw an exception.
       at Emgu.CV.Image`2..ctor(String fileName) in c:\Emgu\emgucv-windows-x86-gpu\Emgu.CV\Image.cs:line 144
       at TEST.Form1.button1_Click(Object sender, EventArgs e) in c:\documents and settings\laci\my documents\visual studio 2010\Projects\TEST\TEST\Form1.cs:line 28
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
       at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ButtonBase.WndProc(Message& m)
       at System.Windows.Forms.Button.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at TEST.Program.Main() in c:\documents and settings\laci\my documents\visual studio 2010\Projects\TEST\TEST\Program.cs:line 18
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: System.DllNotFoundException
       Message=Unable to load DLL 'opencv_core242': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
            at Emgu.CV.CvInvoke.cvRedirectError(CvErrorCallback errorHandler, IntPtr userdata, IntPtr prevUserdata)
            at Emgu.CV.CvInvoke..cctor() in c:\Emgu\emgucv-windows-x86-gpu\Emgu.CV\PInvoke\CvInvoke.cs:line 166
asked on Stack Overflow Dec 14, 2012 by Laci • edited Dec 14, 2012 by Soner Gönül

7 Answers


Since Emgu.CV is just a .NET wrapper (see http://en.wikipedia.org/wiki/Wrapper_library), you need to put the native .DLL files of OpenCV in your application output directory.

You can find the required files by downloading the corresponding version of OpenCV at http://sourceforge.net/projects/opencvlibrary/files/opencv-win/2.4.2/OpenCV-2.4.2.exe/download

answered on Stack Overflow Dec 14, 2012 by Didac Perez Parera • edited Sep 19, 2017 by Nisarg

I will save you all a lot of time. for EMGU CV version 2.4.* the missing dll is "nvcuda.dll" which is not part of the Binaries of EMGU but its usually located in system32 folder (maybe you need to have nvidia driver installed, if not just look for the dll online)

answered on Stack Overflow Oct 7, 2014 by Dani Gelmanovich

You might solve this problem by Using Dependency Walker -> http://www.dependencywalker.com/ on "opencv_core242.dll" to find any missing DLLs.

For me, It show that I didn't has tbb.dll as Thread here tbb.dll not found

Just download from https://www.threadingbuildingblocks.org/ and copy tbb*.dll to working directory or "System32" it will be fine

answered on Stack Overflow Mar 4, 2014 by Kookkoog • edited May 23, 2017 by Community

Old one, but I had the same problem. Turns out that 2.4.0 has GPU integration and if you don't have an Nvidia card, nvcuda.dll is missing and opencv_core242.dll fails to load. Tried everything, the only solution was to go back to 2.3.0 and everything worked fine.

answered on Stack Overflow Mar 20, 2014 by smirkingman

Exactly as the error states - it can't find the native DLL in the working directory of your applcation. Make sure the opencv_core242.dll library is copied to the output directory and working directory of your application.

answered on Stack Overflow Dec 14, 2012 by Vaughan Hilts

Download dependency walker from http://www.dependencywalker.com/ and open the .dll claiming to not load. Then look for the dependencies, if one or more are missing from the directory of the app of even your system folder (system32 or syswow64) then they need to be in there.

answered on Stack Overflow Apr 28, 2014 by Inammathe • edited Apr 28, 2014 by Maks3w

here are proper steps to solve the problem.

visit : https://sourceforge.net/project/emgucv/emgucv/2.4.2/
download specific version of emgucv 2.4.2 according to your operating system like for windows x86 you can download : libemgucv-windows-x86-gpu-

install it some where like C:\Emgu after that go to C:\Emgu\emgucv-windows-x86-gpu\bin\x86 and copy all opencv dll files and paste it in your application exe output directory.

  • to remove unnecessary opencv dll files you , run your application and then press ctrl+A and try to delete the files , those files which are used by your app you will not be able to delete as your app is running and they are in use and the reset unused dll files will be deleted , other than that you can use dependency walker app (http://www.dependencywalker.com/ ) which is outdated may or may not work
answered on Stack Overflow Aug 1, 2019 by user889030

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