can not send through port 25

[dave]

I am unable to send email using any email software
(recieving is OK)..... I am also unable to connect via
telnet to smtp mail servers using port 25 (telnet
mail.xxx.com 25).... So some how Windows appears to have
closed port 25 on outgoing requests.

Thanks in advance,
Dave

 

[David Jones]

What anti-virus or firewall/security programs do you run,
or have ever been run on this machine?

 

[Dave]

Just NAV Corp edition and no Firewall software. It has
been verified that The Microsoft Firewall is off also...

It was working and just stopped.

Thanks,
Dave

 

[Matt DuBois [MSFT]]

This could also be your ISP. Some ISPs block port 25 to anything but their
own mailservers. If you can telnet to port 25 on their mailservers, but
nowhere else, then that is the problem.

 

[dave]

no.... tried that I can not telnet to their smtp server.
They verify it should work.

Thanks,
Dave

 

[Matt DuBois [MSFT]]

Windows itself wouldn't block an outgoing packet, even if the internet
connection firewall was turned on. Are you familiar with how to do a
network trace? It would be interesting to see if the packets are making it
out onto the wire at all, to narrow down if it is software on your machine
or something in the network between your computer and the network as a
whole.

How is your computer connected to the internet? Directly, or through
another device (ICS, "broadband router", etc)?

 

[dave]

Hi... I know how to tracert.... and that works fine. I
do not know of a way to trace the rout while using a
specific port (25) so I do not know how far it is getting.

This computer is connected to the internet simply with a
cable modem.

Thanks,
Dave

 

[Pat M]

Some accounts require that you use the secure login. It may be called
something different in your account set-up. Check this out. If need
be, create a new account and you should be able to reconfigure any
settings that may have been different on the other account.

 

[Matt DuBois [MSFT]]

The next thing to do in that case, is to see if there is something on your
computer intercepting the packets before they leave, or if the problem lies
between your cable modem and the other server. Do you have a dial up
account with a different ISP that you could connect to and try to connect to
port 25 of a server? That would tell you for sure if the problem is with
your ISP or software installed on your computer. Likewise, if there are any
other computers connected through the same cable modem in your house that
are able to connect, that would tell you as well.

Barring either of the above, the next step would be to take a network sniff.
If you can show that the transmission is going from your computer to the
cable modem, you will have the ammunition you need to get your ISP to look
into it. If you don't see that, then you'll know its time to look really
hard at software you've installed lately, and possibly run a spyware/ad
removal tool. Ethereal is one popular free tool used for taking network
sniffs, and there are many others, free and not. Just start it up and try
to connect. What you should see is a packet with a source IP of your
computer, and a destination IP of the remote computer/port 25.