Referenced DLL Cannot Be Found When Running Application

Question

I have a weird situation with some code that I inherited at work. Their application is a multi-project solution, with several of the solutions being (code) pieces of the MS Enterprise Library (not sure which version).

They also have an existing C++ (unmanaged) application which has a bunch of DLLs. One of these DLLs is built in a separate solution, both in 64-bit and 32-bit flavours.

The main application has a reference to this DLL, and calls a couple of static functions (I can see intellisense, even). I can compile and build the main application EXEs, but when I run it, I get an exception that this DLL from the unmanaged code (lets call it CPlusPlusCode.dll cannot be found:

FileNotFound Exception was unhandled: Could not load file or assembly 'CPlusPlusCode.dll' or one of its dependencies. The specified module could not be found.

I'm quite stumped, because I can compile the code, see intellisense for the imported classes, and dig into the DLL in the object browser. I even made sure there's a copy in the \\bin\\Debug folder (although I don't see why that would make a difference). This is for a Windows Forms application.

Also, if it matters, I had some build issues related to x86 vs. x64 for different projects; I think (hope?) that this is not related to that, but I solved that by using the Configuration Manager to build everything as x64.

Answer 1

检查GAC，如果需要，您可能需要添加它或在其中注册DLL。

Answer 2

I had this problem with a project, it all works ok from Visual Studio and most of my times running the project locally on my machine. But because of the unmanaged code I needed specifically allow the project to be executed with correct permission levels.

So have a look in the manifest file, that enough permissions etc exist.