Hello,
Check out the following article which details the troubleshooting steps for each 401.x error:
Troubleshooting HTTP 401 errors in IIS
http://support.microsoft.com/kb/907273
Since you installed Coldfusion, I would check the Web Service Extension settings to ensure everything is Allowed that should be, and that your Handler Mappings are configured correctly in your site's properties, as ColdFusion tends to try to take over all handler mappings with a wildcard entry.
Hope this helps!
Brock Hensley
Technical Support Representative
http://www.ServerIntellect.comManaged Servers, 24x7 U.S. Support, Web Hosting Solutions.