No, but I have developed some custom modules of my own, so I have a DEV instance of the website. The Smith Cart .ascx pages all contain references to the compiled DLLs they rely on, and every last one of them is in the bin folder ..... except this one. Result: when I do a Build from Visual Studio, it throws that error. If I exclude the ProductMatrix ascx file, the build succeeds. But that's a bit like amputating a finger to cure a hangnail. :-)