Cannot access Web admin

I am a ejabberd newbie, so my question will sound like a kind of stupid.
I am currently installing ejabberd on a clustered environment (2 nodes: windows server 2008).
It was possible for me to configure through web admin at the very begining of the install....
But now, after a while, I think I properly configured the clustering (so that I can see both node running when I am doing "mnesia.info()."..I can even control each of them "mnesia.stop().", "mnesia.start()."
The big issue now is that, when I want to acces to the web admin console (http://localhost:5280/admin)....IE does not allow to access this page. I turned off every firewall level (domain, private & public profile) and IE Enhance" Security (for both user and administrator)...NO success.
I would be very grateful to those that could help me to resolve this.
Clapou