Unable to load libtensorflow.dll assembly on ASP.net 4.6

Describe the bug
When I go to instantiate a new TFGraph instance, the application will report back and claim that it is unable to load the libtensorflow.dll assembly. However, unlike other similar issues, I have confirmed that the libtensorflow.dll file IS PRESENT in the bin/Debug folder. The interesting part is that when I locally run the API, this issue is nonexistent. However, after using Web Deploy 3.6 and pushing the code to an actual IIS server for debugging, the application is unable to load the assembly. In fact, even in the web deploy target server's bin/Debug folder the libtensorflow.dll is present.

To Reproduce
Launch a ASP.net web API with TensorFlowSharp installed via NuGet. First run the API on your local machine to ensure that the sample code for loading a pre-trained model on the main Github is working (I'm using the same code snippet). Next publish the API to an IIS server (the server I am publishing to is in a data center so I must RDP into it). Finally, load a protobuf file of your choice with sample data and attempt to run the code. It should come back and say that the assembly libtensorflow.dll could not be loaded.

Expected behavior
The application should be able to create a new instance of TFGraph.

Screenshots

Desktop (please complete the following information):

• OS: Windows Server 2016
• Browser: Google Chrome
• Version: TensorFlowSharp v1.9

[Andy-Wilkinson]

I've had issues with the .NET DLL loader searching in the wrong directory for the libtensorflow.dll library dependent on how the executable is started. As a test could you try moving the libtensorflow.dll library into a few other locations. My first thoughts would be,

• the root webapp folder
• the 'bin' folder (not under 'Debug')
• somewhere on the 'PATH' environment variable (or add the 'Debug' folder to PATH)
• the 'Windows/System32' folder should also work

NB: The last two aren't ideal in a server-based environment, but might help prove that the dll location is the issue. I don't have enough experience with IIS to say for sure, but I suspect either ASP.Net or IIS have some configuration for DLL search locations - might be worth doing a bit of searching for this.

[forbeshawkins]

This error message can be a little deceptive. In my case, it turned out that I needed to install the C++ Redistributable package on the server.

[SignalRT]

I had a similar issue with a WinForms .NET 4.6. I need to force the project to 64x. The library is a 64 bit library.

[MythSHen]

u need to use net 4.7.1 or 4.7.2
use x64

[ZYT5ting]

I have encountered this problem before, the model (pb file) conversion has a problem, you can use the pb model automatically downloaded by the ExampleObjectDetection project to verify the problem.