Tcp/ip port security issue...

[Guest]

I have a small plain Windows 2000 Server (not Advanced, not Data Center).

until recently, it didn't really have a purpose other than for training.

It has all the latest updates from microsoft's Update site and it is now a
member server of an NT 4.0 domain.

I have a client/server type of app on the Win2k server that is not
functioning.

The tech support rep for the app says that the app relies on and uses
certain Tcp/ip ports.

To test the functionality of the ports, he had me use telnet as follows...

At a workstation command prompt I typed...

TELNET servermachinename portnumber

and the tech support rep was satisfied with the output response.

At the win2k server command prompt I typed...

TELNET workstationname portnumber

and the response is COULD NOT OPEN A CONNECTION TO HOST ON PORT number
: CONNECT FAILED

so the tech support rep says this is why my client/server app is not
functioning, but he didn't tell me how to fix it.

I check in the properties of my ethernet connection, in the properties of
the tcp/ip protocol and there isn't any tcp/ip filtering enabled. I do not
have a 3rd party firewall app on the win2k server.

Does anyone know where else I could check that could affect tcp/ip ports?

Thanks

 

[Dave]

not very helpful tech rep from the sounds of it... i'd ask for my money
back.

but beyond that. try going to the workstation and doing the telnet command
that he wanted you to do from the server. this would test to see that the
app he is trying to connect to from the server is really running, is
listening on the right port, and that the tcp/ip stack on the workstation is
at least minimally working. if this test doesn't pass then i would guess
that the app isn't running or can't open it's port, maybe something else has
that port already, or some security setting is preventing it from listening,
etc...

if that test does work, try it again from a different workstation. this
would test the external network connection to the workstation... if that
works then the problem may be from the server, maybe bad dns/wins or
something else that prevents it from getting to that workstation. if it
doesn't work then there is likely something wrong with the network
connection/router/dns/wins for that workstation.

 

[Phillip Windell]

To test the functionality of the ports, he had me use telnet as follows...
At a workstation command prompt I typed...
TELNET servermachinename portnumber
and the tech support rep was satisfied with the output response.
Fine.

At the win2k server command prompt I typed...
TELNET workstationname portnumber

and the response is COULD NOT OPEN A CONNECTION TO HOST ON PORT number
: CONNECT FAILED

That isn't supposed to work. The Client Application is a *client*
application,...it is not supposed to listen for incomming
connections,...that is what the server is supposed to do, and it sounds like
it is doing that.

It sounds to me like the Client Application is not installed or configured
properly on the workstation.