Lienne 0 Newbie Poster

I've been having trouble with a strange popup box showing up when I try to access my IIS server through it's IP address (even on the host computer itself). If I enter the host computer's user/pass it will work fine, but unfortunately the other users on my intranet have to do the same thing (which is definitely not favorable). Sometimes (i've been installing the same app on many systems) this prompt does not appear, however. I've been trying for months to isolate why, to no avail. I'm new to IIS/MSSQL, so I'm not even sure what I'm looking for. Sometimes it seems like a database issue (only prompting when a script tries to access it) but other times it will prompt simply for browsing a folder.

I need so much help! Thank you SO much in advance!

You can view a screen shot here: http://lienne.net/box/images/prompt.png