Can't access an imported library c#.net Visual studio

Basically I've created a project from 0 using Visual Studio 2010, a simple aspx (with his aspx.cs and .designer behind) which needs to call a library located in the same project folder /bin/libraryName.dll.

I right-clicked on my project and added the reference. I even added the following lines to make sure my project could see the .dll file:

if (File.Exists("B:\\mk2015\\web\\Simposium2015\\bin\\DecoderEndeavour.dll"))
{
   Response.Redirect("Found.html");
}

Inside the /bin/LibraryName.dll path on my Project Explorer I could see now a LibraryName.dll.refresh file was created, that simply has in him the path pointing to where the .dll is located.

I tried to execute the code:

LibraryName.Class1 Decoder = new LibraryName.Class1();

And I got the following error:

The system cannot find the file specified. (Exception from HRESULT: 0x80070002). From the FileNotFoundException.

I'm completely lost, in some way my code is able to verify a file is there, he can see it, but somehow it's not correctly linked to some part of the project as then it doesn't find it when trying to create a class declared inside the library.

Can anyone help?

Thanks!