使用服务时出错：“YYY.YYY”类型中不存在类型名称“AAA”

I'm trying to consume a WCF 4.0 service in my application. I built, tested, and deployed the service from the ground up. The service works in the WCF test client and can be consumed in any other test project I built. The problem is this one particular application... the only one that matters as it's the reason I built the service.I'm trying to consume a WCF 4.0 service in my a