Silverlight Issue , Operation named 'CreateUser' does not conform to the required signature.

当项目从一个PC移到另外一台电脑的时候出现这个错误，网上有人也有帖子说这个问题 ，原因是两台电脑的ria service不一致：

http://forums.silverlight.net/p/224513/541507.aspx

解决方法：

installed the RiaServices SP1
http://www.silverlight.net/learn/advanced-techniques/wcf-ria-services/get-started-with-wcf-ria-services