¿Cómo solucionar la excepción dllnotfound al agregar complementos en Unity?

How to fix dllnotfoundexception when adding plugins in Unity?

You have a few issues. First, the C++ function itself needs to be declared extern “C”, not just the header for it. It also needs to be declared as a shared export, which is different per platform. In your cpp, replace line 3 with:

For others who may face this problem, if you have more than one dll, you need to put the secondary dlls at root level of the Unity editor (e.g. C://Program Files//Unity//Editor) and the actual referenced dll from script into plugins folder. This worked for me. A better place for the dll files would be in the project folder.

In C# you should remove any lib prefix in your library name, for example: Cheers. Plugins should all stay in a folder called Plugins. The architecture your dll is built for (x86 or x86_64) must correspond to the architecture version of Unity Editor.

However, it seems to me there is an issue with Unity not accepting a UWP DLL. I’m glad that you find the way of having your DLL working in Unity! And thank you for sharing your findings. On the other hand, even taking into account that a build for Hololens uses UWP, doesn’t necessarily mean that Unity is able to use UWP plugins.

And I have verified the dll exist in Appname_Data/Plugin directory in my standalone app. The dll (test.dll) is produced by visual studio 2015 (debug and x64). It depends on many other dlls which I copied along with test.dll into my unity project.

So press Build > Build APK and locate the path where the file has been built to. Rename the .apk to .zip and uncompress the package. You will see a lib folder with your .so files compiled for all the compatible architectures. Copy these into Unity and set their appropriate platforms and you’re finally good to go.

I’m guessing the reason for it not working on the standalone player is because you have some DLLs in your unity project that your DLL depends on but they’re marked as compatible with editor only, so Unity doesn’t copy them to your plugins directory of the standalone build.