Have LAN Connection but no internet access

[Jackie]

We have 5 computers all networked with LAN cables. Computers B,C,D and E all access a dial up modem to the internet via computer A. Up until recently, all worked well. Now computer B whilst able to access all the other computers in this home network, is unable to access the internet.

Computer B can see the dial up network connection, as connected, as well as the local area connection, but internet and email are not available/accessible.

Have replaced the Lan Cable, disabled the firewall, checked internet connection sharing and run anti virus AVG.

Computer B - as are all 4 other computers, is using Windows Home XP Service Pack 2.

What else can we do?

Please can someone help.

[Calum]

What happened before computer B stopped connecting?

[Rob Pomeroy]

What else can we do?

At this stage, you should think about buying a suitable router.  Much better performance, easier to configure, and more suitable to a small workgroup since PC A does not need to be left switched on.

[Jackie]

Nothing, that I am aware of... it is my daughter's computer and it literally was working fine one day and the next, when she went to access the internet, she couldn't. My husband and I have tried everything we can think of. To the other reply, thank you... however, because we have children connected, it is actually better if they have to route through computer A, as computer A is my husband's and we don' want them accessing the net, during peak hours, and without our knowledge.

[viking]

What error do you receive?
I would look to DNS and Gateway record of the computer with the problem (should be the same with the settings of the others computers that connect to internet by computerA).
Do the following:
start->run->cmd (enter)
ipconfig /all >>c:\outipconf.txt

Copy the content of outipconf.txt here, show us the ip settings.

Do you use a proxy program or just plain Internet Connection Sharing on computerA?

[Jackie]

Only error message is after trying to connect and that is "Cannot find server or DNS error". We are using Internet connection sharing, and will send you ip info shortly

[Jackie]

Thank you for your interest and willingness to help, it is appreciated. I continued reading up on the internet, after you asked what error message do I get, and decided to follow some advice that I found. Don't quite know the reasoning behind what I was advised, but it worked. I was advised to put in a preferred DNS server 209.193.72.2 and an alternate DNS server 209.193.68.2.

As stupid as this may sound, are the preferred and alternate DNS "addresses" safe, in any and all ways and if not would you mind advising please?

[Rob Pomeroy]

Where did you get these DNS server addresses from, Jackie?  The best addresses to use would be the DNS servers run by your ISP.

[viking]

Jackie, you have a computer that does not work and some computers that work. Use the DNS from the computers that work also on the computer in your network with the problem.

[phoenix910]

By the way, I would advise switching to ADSL rather than Dial-Up, it's a lot more error free and easier to sort out when you have trouble like this. One suggestion I would have would be to (rather than have computer A on when you want to and all other computers hooking up to it) - if you want to restrict their hours of access - is to switch to ADSL for a start, but then but what they call a network switch or router, and connect all the computers to this, but the modem to this as well, as opposed to through a computer. This means that anybody can access the internet at anytime, which is not what you want to happen. This is why they have programs that can restrict internet access times and websites, which can be put in place on all of their computers. Just a suggestion.