Issue browsing secure intranet web application

Hi,

I have an secure intranet asp.net application. The application runs fine on the intranet from most of the computers i have tried on. (I work in a corporate env) The problem is that I get a page cannot be displayed message when I try to access the url from 2 machines in the intranet. Apparently, 1 is my machine and the other is of my collegue. I have drawn a blank on what the issue could be. I have even setup a sample website alongside my application on the host server and the sample website works just fine. Its just the problem with my web application. Could any one suggest how I can debug this issue. Appreciate any help on this.

Thanks, Amit.
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