I'm having the same problem. My guess is that it may be the cache, but I don't know.

In my case I wish to change the portal alias from "www mydomain com/portal " to "www mydomain net"  (with periods where the spaces are). The redirect to the DNN application directory is handled by a script in the root directory. When I edit the HTTPalias field in the portalAlias table of the DNN database my application fails. When I restore the entry in the field the application continues to fail.

Any help would be appreciated.

Thanks for the response. As you suggested, restarting the application by updating the web.config file did indicate that part of the problem was the cached value for the web portal - by doing this I was able to restore the portal alias to the working version (before I changed it).

Still I have this problem:  I have two domain pointers: www.albigen.com and www.albigen.net - both point to my website root. I want www.albigen.net to be the DNN application.  The physical directory of the DNN installation is <root>/portal.  The hosting provider will not point domain names to a subdirectory, so  I have a script in the index.aspx file in the root directory of the site that reads: 

if (Request.Url.ToString().Contains("albigen.net"))

{

Response.Redirect("/portal");

}

The current portal alias is: www.albigen.com/portal

I wish to change the alias to www.albigen.net

If I make this change in the HTTPalias field in the portalAlias table, the application fails.

However, the portal name will work if I use www.albigen.net/portal

So how do I get rid of the subdirectory in the portal alias?

Thanks very much.