IIS 401 Error Using Windows Auth Locally
Posted by jheyse on January 22nd, 2009
Today, Chris came to me with one of those WTF issues… He is developing a SharePoint application which communicates with WCF services hosted in a separate IIS Web Site on the same physical machine. Both websites are bound to the same IP Address and are using host headers to distinguish themselves. Also, both Web Sites disallow anonymous access and enforce Windows Authentication. Chris was working on deploying his services and invoking them from the SharePoint site. He first tested the services from his local dev machine and everything worked. When he published the code to the SharePoint instance on server the code was failing with a HTTP 401.1 error. Invalid credentials…
To get the root of the problem we created a simple HTML file and placed it in the root of the directory. We were still getting the same error. The next step was to enable logging in IIS which provided us with a little more information, including the exact error 401.1 / 2148074252. After some head scratching and googling, we ran across this knowledge base article KB896861. A quick modification to the registry, a reset and we were back in business.
