The Web application at  could not be found. Verify that you have typed the URL correctly. If the URL should be serving existing content, the system administrator may need to add a new request URL mapping to the intended application.

收到此错误时一般想到的都是检查URL是否正确。

本人在2008R2下遇到过一次，原因不是URL的问题。在之前的调试中为了能在调试中即时修改改成了X86，导致了上述错误，不知是否是SharePoint的bug。

记录下来分享。