I've been trying to get ASP.NET 4.0 to work on Windows Server 2003 R2, 64-bit OS, IIS 6.0 in 32-bit mode. The latest thing I tried in the process was to run aspnet_regiis -s "W3SVC/12345/root"
to try to change the version of ASP.NET being run on the site. This seems to have worked, and ASP.NET 4.0 code is now running properly.
However, this seems to have caused a new problem. IIS is no longer recognizing default documents of any type! I have Coldfusion installed on the server and it's default documents are not working either. When I visit http://www.myserver.com or http://www.myserver.com/subfolder, I get "404, file not found". But when I visit http://www.myserver.com/index.cfm or http://www.myserver.com/subfolder/Default.aspx, it works. I've looked at the "documents" tab in the site properties in IIS and both index.cfm and default.aspx are listed there. Why won't IIS recognize them? This was working before, how did I break it?
Edit 1:
I've found that if I create a new site in IIS with all the same settings but running on a different port - ie. http://www.myserver.com:8080/ - the default documents for ColdFusion work again. However ASP.NET default documents still don't work on the newly created site. I have to manually type in http://www.myserver.com:8080/subfolder/Default.aspx instead of http://www.myserver.com:8080/subfolder/.
Did you create Virtual Directory of the folder 'subolder'? If not then please create the Virtual Directory and then set the default and then try.