Are you sure there isn't some sort of port-forwarding problem. Your IIS is clearly working given that you said it works internally, but the errors you describe sound like your outside router isn't touching the IIS server at all.
If you go home and telnet to:
telnet 195.147.x.x 80
and it manages to connect () and you then type:
GET
and it returns back html code like:
--------------------------------------------------------
HTTP/1.1 400 Bad Request
Server: Microsoft-IIS/5.0
Date: Tue, 22 Mar 2005 23:05:59 GMT
Content-Type: text/html
Content-Length: 87
<html><head><title>Error</title></head><body>The parameter is incorrect. </body>
</html>
Connection to host lost.
--------------------------------------------------------
then you know it's hitting the IIS server, if you get nothing or the port seems to be closed off, then it's most likely a problem at the edge of your network.
You can also, from your LAN, go to
and do the "Shields UP!" test, it can tell you which ports are open and forwarding on your router.