Could not load file or assembly ‘AjaxMin, Version=4.97.4951.28478, Culture=neutral, PublicKeyToken=21ef50ce11b5d80f’ or one of its dependencies. The system cannot find the file specified.

Matty's suggestion to check the sample project sent me back to the directory where I'd unzipped it, then checked the file AjaxControlToolkit.Binary.NET40.zip, which had the AjaxMin.dll file in it. I had admin move the file to C:\Program Files\Microsoft Visual Studio 10.0\VB\Bin (I don't know if that directory matters, it works for me), then in VS added the DLL as a reference to the project. The few errors I've gotten since are nothing to do with ajaxmin.

(AjaxControlToolkit zip dosyasindaki AjaxMin.dll dosyasini secip Bin klasorune kopyalayiniz.)