Subsonic: Connection has been reset

Hi,
I have Subsonic running on http://media.indoforum.net
Running on Windows Server 2012 as user on port 80.
The problem is some of the users (from Internet) when they access, their browser returned 'Connection has been reset'
They can PING the host (no problem) but they just can't open the site.
But I myself don't have such problem. How can I get this fixed?
Thank you.
I have Subsonic running on http://media.indoforum.net
Running on Windows Server 2012 as user on port 80.
The problem is some of the users (from Internet) when they access, their browser returned 'Connection has been reset'
They can PING the host (no problem) but they just can't open the site.
But I myself don't have such problem. How can I get this fixed?
Thank you.