Avoid being prompted for credentials when accessing Windows Integrated Authentication sites using Firefox

I recently authored a simple ASP.NET internal website at my office to act as a repository for proposed enhancements for an upcoming release of our product. (Visual Studio .NET 2005 made authoring the site really quick and easy, such that the small amount of dev time I needed to put in to create the site was worth the gain in usability over a solution like Excel or Access.)

Since only internal employees would be using the site, I decided to set it up to use the Windows Integrated Authentication provided by IIS 5, so users of the site would automatically be logged in using their domain credentials (rather than being prompted for a set of credentials).

This worked great when accessing the site in Internet Explorer. However, when using Firefox, I would get prompted by Firefox for a set of credentials when first accessing the site. Entering my domain username and password did allow me to access the site successfully.

I wanted to avoid the login prompt with Firefox, so I Googled for firefox integrated authentication prompt. This turned up a couple of good results that pointed me to the solution:

• In the Firefox Location bar, type about:config and press enter.
• In the Filter bar that appears, type Network.automatic-ntlm-auth.trusted-uris and press enter.
• Under "Preference Name", double-click on Network.automatic-ntlm-auth.trusted-uris, and enter the name of the web server machine in the dialog that appears.

Now users are able to access the site without being prompted for credentials -- Firefox uses Integrated Authentication and automatically uses the user's domain credentials to log in.