Set Custom Path to Referenced DLL's?

From this page (untested by me):

Somewhere in your program's initialization (before you access any classes from a referenced assembly) do this:

AppDomain.CurrentDomain.AppendPrivatePath(@"bin\DLLs");

Edit: This article says AppendPrivatePath is considered obsolete, but also gives a workaround.

Edit 2: Looks like the easiest and most kosher way to do this is in the app.config file (see here):

<configuration>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <probing privatePath="bin\DLLs" />
    </assemblyBinding>
  </runtime>
</configuration>

From Tomek answer at: Loading dlls from path specified in SetdllDirectory in c#

var dllDirectory = @"C:/some/path";
Environment.SetEnvironmentVariable("PATH", Environment.GetEnvironmentVariable("PATH") + ";" + dllDirectory)

It works perfectly for me!

Here is an other way to proceed without using obsolete AppendPrivatePath. It catches a kind of event "associated dll not found" (so it will be called only if the dll is not found in the default directory).

Works for me (.NET 3.5, not tested other versions)

/// <summary>
/// Here is the list of authorized assemblies (DLL files)
/// You HAVE TO specify each of them and call InitializeAssembly()
/// </summary>
private static string[] LOAD_ASSEMBLIES = { "FooBar.dll", "BarFooFoz.dll" };

/// <summary>
/// Call this method at the beginning of the program
/// </summary>
public static void initializeAssembly()
{
    AppDomain.CurrentDomain.AssemblyResolve += delegate(object sender, ResolveEventArgs args)
    {
        string assemblyFile = (args.Name.Contains(','))
            ? args.Name.Substring(0, args.Name.IndexOf(','))
            : args.Name;

        assemblyFile += ".dll";

        // Forbid non handled dll's
        if (!LOAD_ASSEMBLIES.Contains(assemblyFile))
        {
            return null;
        }

        string absoluteFolder = new FileInfo((new System.Uri(Assembly.GetExecutingAssembly().CodeBase)).LocalPath).Directory.FullName;
        string targetPath = Path.Combine(absoluteFolder, assemblyFile);

        try
        {
            return Assembly.LoadFile(targetPath);
        }
        catch (Exception)
        {
            return null;
        }
    };
}

PS: I did not managed to use AppDomainSetup.PrivateBinPath, it is too laborious.