port 80 closed, need your help

I am having very strange problem. On one of my machines (A)
I have w2k server, using IIS. I have a website there for over a year.

It stopped working yesterday.I noticed that port 80 is closed. I did not make any changes so I thought my ISP (DSL) closed it. I called my ISP and they told me that they did not block any port.
More Over I hooked up my DSL to other computer(B) and port 80 was open.

I thought may be it is the router, i connected straight DSL to computer , but still port 80 is closed

So I thought probably some virus on my machine. But I also have another ISP (cable modem) when I connected cable modem to the same computer (A) port 80 was OPEN. That mean Computer is fine too. I don't know what is going on.

It basically the combination of DSL and computer (A), when problem occurs.....

Your help will be greatly apprecaietd...

Thanks

no virus that I know of, normally they try to "open" connections instead of blocking them
I'll move this to the IIS forum and see if you can get help there, if it's a virus just move it back mods.

The question that comes to my mind is "how did you determine port 80 was closed".

If you could find out it was blocked you should be right where you can open it.

I go to

http://www.grc.com/x/ne.dll?rh1dkyd2

to see what ports are open or closed.... very useful tool..

well actually

https://grc.com/x/ne.dll?bh0bkyd2

then click on proceed

According to shieldsup! my computer is insanely secure; so secure, only one port was open.

OK. Then look at the settings in your router, and in any firewall software or ISA server, or any changes to the IIS configuration. Try from another computer inside your firewall.

Thanks for your reply.

For trouble shooting purpose I have disabled the firewall, so fire wall can not block port 80.
I also have taken the router out and connected modem staright to my PC.....But still when I connect through DSL my port 80 is closed, and when I connect through Cable it is open.......

Windows...
very usefull tool as well, And since you already have it installed, why not use it?

Windows can do pretty much everything linux/unix can. It's just not well documented or it's been forgotten and buried by those oldtimers who knew the languages and idiosynchrosies.

try this at a command prompt
NETSTAT -a -n

or

NETSTAT -s

or

NETSTAT -r

or

NETSTAT -o

to do real time viewing of all connections, try NETSTAT -a 5
That's give you a running update every 5 seconds, showing all active connections.

for the dns cache, try
ipconfig /displaydns
To get all your IP info and dns servers, leases, etc, try ipconfig /all


To keep a record or log of each output, or create a system report, add
>>c:\MyReport.txt
after each command. That will add to the file instead of overwriting it.
To create a new file each time, overwriting the original, just use a single >
>c:\MyReport.txt
Use DOS shortnames in the save path though or you'll end up with a blank file. Otherwise, if you don't specify a path, it'll go to documents and settings in the active users account.

There's a lot more usefull commands available in the windows 2000 resource kit and in the GnuWin tools collections.
And a ton of hidden info on google if you know how to find it.

Thanks ..i tried some of your commands


C:\>NETSTAT -a

Active Connections

Proto Local Address Foreign Address State
TCP irfan-qqsqq665e:smtp irfan-qqsqq665e:0 LISTENING
TCP irfan-qqsqq665e:http irfan-qqsqq665e:0 LISTENING
TCP irfan-qqsqq665e:epmap irfan-qqsqq665e:0 LISTENING
TCP irfan-qqsqq665e:https irfan-qqsqq665e:0 LISTENING

*******

C:\>NETSTAT -n

Active Connections

Proto Local Address Foreign Address State
TCP 127.0.0.1:1036 127.0.0.1:1037 ESTABLISHED
TCP 127.0.0.1:1037 127.0.0.1:1036 ESTABLISHED
TCP 192.168.1.2:1043 216.155.193.164:119 ESTABLISHED
**************

I do found out now one thing, If I take router out I
get port 80 open.
But I hooked up same router with other computer and it works fine and give me port 80 open.

I used one another router which is working fine with other computer but when hooked to my this machine gives me port 80 "Stealth"..

For some reason this machine is having problem with the routers.......