TCP/IP Problem

[Jeffrey]

I am having a problem with the dial-up internet connections
on both of my home computers. They are both on a LAN,
connected through a small hub; they each have a dial-up
connection set up; and the laptop has a wireless card to
access local wireless hotspots. Both computers are running
Windows XP Home.
My problem is this: I noticed that some web and internet
functionality was lost about a week ago on one computer.
After checking nearly everything, I found that the problem
was that the dial-up connection was connecting with a
decent-looking IP address, but the subnet mask was
255.255.255.255 (whereas normally I would receive
255.255.255.0). I had just installed SpybotS-D on that
computer, so I uninstalled that--to no avail. I also
uninstalled and disabled my IEEE 1394 connection and
software, which I had recently installed as well. Nothing
helped, so that computer was essentially
Internet-handicapped. I could visit some websites, sign on
to AOL IM sometimes, and could not check email--all,
apparently, because my subnet mask was locked into the
wrong number.
Today, my laptop, which had served faithfully in the
Internet and email capacity in lieu of the other computer,
started having the same problem. I connect by dial-up but
cannot check email, sign onto IM, or visit some websites.
The subnet mask now has become 255.255.255.255 on that
computer, as well. (As a side point, the wireless internet
connection on that computer seemed to develop the same
problem (even though its IP address and all looked fine),
but I have not had time to test and confirm this.)
I have tried evertyhing I could think of, from using
Network Troubleshooter to manually resetting the TCP/IP
settings on the computer by command-line. Using ping and
pathping, I can ping the other computer on the network, but
I cannot ping myself. Neither could I ping the desktop
from the laptop (when the laptop was working fine), but I
could still ping the laptop from the laptop at that time.
So, I have no idea what could possibly be causing this
problem. Any assistance would be greatly appreciated.
-Jeffrey

 

[Chuck]

I am having a problem with the dial-up internet connections
on both of my home computers. They are both on a LAN,
connected through a small hub; they each have a dial-up
connection set up; and the laptop has a wireless card to
access local wireless hotspots. Both computers are running
Windows XP Home.
My problem is this: I noticed that some web and internet
functionality was lost about a week ago on one computer.
After checking nearly everything, I found that the problem
was that the dial-up connection was connecting with a
decent-looking IP address, but the subnet mask was
255.255.255.255 (whereas normally I would receive
255.255.255.0). I had just installed SpybotS-D on that
computer, so I uninstalled that--to no avail. I also
uninstalled and disabled my IEEE 1394 connection and
software, which I had recently installed as well. Nothing
helped, so that computer was essentially
Internet-handicapped. I could visit some websites, sign on
to AOL IM sometimes, and could not check email--all,
apparently, because my subnet mask was locked into the
wrong number.
Today, my laptop, which had served faithfully in the
Internet and email capacity in lieu of the other computer,
started having the same problem. I connect by dial-up but
cannot check email, sign onto IM, or visit some websites.
The subnet mask now has become 255.255.255.255 on that
computer, as well. (As a side point, the wireless internet
connection on that computer seemed to develop the same
problem (even though its IP address and all looked fine),
but I have not had time to test and confirm this.)
I have tried evertyhing I could think of, from using
Network Troubleshooter to manually resetting the TCP/IP
settings on the computer by command-line. Using ping and
pathping, I can ping the other computer on the network, but
I cannot ping myself. Neither could I ping the desktop
from the laptop (when the laptop was working fine), but I
could still ping the laptop from the laptop at that time.
So, I have no idea what could possibly be causing this
problem. Any assistance would be greatly appreciated.
-Jeffrey

Jeffrey,

The configuration you need to use with a dialup connection varies according to
the ISP. If your ISP were to change its setup, including DNS servers and subnet
mask, your computer might detect the change automatically, or you might have to
check the instructions from your ISP.

In this case, I would advise you to start with the instructions from your ISP.
From reading your problem, I am guessing that your problem (lack of
functionality - can't connect to some services or websites) was originally
caused by access to your ISP's DNS servers. DNS is a very basic function
required by computers connecting to the internet. When I used dialup, I found
it good to frequently check and change my DNS servers.

Not knowing exactly what you changed, or in what order, I would simply advise
you to reconfigure everything according to instructions from your ISP. Get
instructions online, by using another computer, if possible. Follow everything
to the letter. Then CALL them online, and ask for the current DNS servers. Add
those into the configuration.

After getting everything working, you can tweak your DNS server usage. You need
to use DNS servers that are logically near the point where you connect to the
internet - which may not be the same point that your ISP connects, so you might
benefit from using different DNS servers.

But don't try to second guess your dialup configuration otherwise - it isn't
worth it. Trust your ISP otherwise.

Cheers,
Chuck
Paranoia comes from experience - and is not necessarily a bad thing.