HttpCode

I came across a weird problem with IE and the way it automatically passes credentials to an intranet site. Basically we had an intranet site in the form of http://<intranet name>.<domian name>, e.g. http://intranet.httpcode.com.

Now if users set their homepage directly to this, they would be prompted to authenticate on the first page load, however if you first browsed to another site first (didn’t matter what it was, it could be google.com), then the intranet URL, IE would not prompt you to authenticate, it would work as expected. It’s as if IE didn’t know that the intranet site was in the Intranet zone on the first load.

I found this KB article, I’ve highlighted the interesting bit below:

http://support.microsoft.com/kb/258063

• Internet Explorer must consider the requested URL to be on the intranet (local). If the computer name portion of the requested URL contains periods (such as http://www.microsoft.com and http://10.0.0.1), Internet Explorer assumes that the requested address exists on the Internet and does not pass any credentials automatically. Addresses without periods (such as http://webserver) are considered to be on the intranet (local); Internet Explorer passes credentials automatically

We ended up just creating the intranet site without a period, i.e. http://intranet this seems to work, in that IE on the first load passes the credentials on properly.

I’m not really sure what to say about this problem (if it is really a problem), I couldn’t find any relevant references on the web about it. Any ideas?