Mystery internet loss after 5 mins?

Mark M · 6 Feb 2006 at 11:11

We are currently running 8 computers, all xp pro, on a windows 2003 server. Everything has been running fine for more than a year but recently one computer has been having trouble connecting to the internet. For 5 minutes the machine will connect to the interet fine, as normal, and then after the 5 minutes(approx) it kicks it out. Logging off then on again doesnt solve the problem but restarting the computer works for the 5 minutes or so.

Here is a quick diagram of how the network is set up.

Ive tried everything I can think, which unfortunatly isnt a great deal, including system restore, removing all the dns settings etc, firefox instead of IE plus some other things and none of them worked. I was starting to think that perhaps there is a conflict somewhere but what and where I have no idea.

Any suggestions would be greatly appreciated and if you need anymore info that I have missed then please ask.

Thanks for any help.
Mark

Mark M · 6 Feb 2006 at 11:14

Forgot to mention that I dont "think" that its a virus/spyware as I have tried avg anti-virus, adaware and the microsoft antispyware on it and none of them have found anything. AVG has been installed since day one and been updated daily and never found anything.

Burbleflop · 6 Feb 2006 at 11:19

Is it always the same PC? When it messes about, can it still access network resources (shared folders, printers and so on)? Can it still ping the router? Can it ping anything on the internet?

Mark M · 6 Feb 2006 at 11:23

It has no problem accessing mapped drives, browsing the whole network etc. It has a local printer so thats not a issue.

I will try and ping the router now and report back.

Mark M · 6 Feb 2006 at 11:40

It will ping the router no problem as well as any other machine on the network.

Burbleflop · 6 Feb 2006 at 11:55

I'm stumped then, I was hoping that it wouldn't be able to ping the router and could suggest changing the network card or updating the drivers. Infact, try that anyway if you can?

Can it ping machines on the internet when it is buggering about?

Mark M · 6 Feb 2006 at 12:10

How do I go about pinging a machine on the net, what IP do I use? Excuse my lack of knowledge.

Burbleflop · 6 Feb 2006 at 12:11

Try pinging jolt.co.uk

Mark M · 6 Feb 2006 at 12:12

As far as network cards and drivers go, all the machines are dell, same model etc with on board network cards. I didnt think there would be a problem with this as you can access the network files and folders, just not the internet.

Burbleflop · 6 Feb 2006 at 12:15

Accessing files on the network can be done using NetBios so that wouldn't prove that your TCP/IP stack (ie the bit that you need to get onto the internet) is still working but as you can ping machines that isn't the case.

It's worth trying anyway.

Mark M · 6 Feb 2006 at 12:26

Ok just tried to ping jolt.co.uk and it worked no problem. I also tried the bbc.co.uk and it worked. What does that mean?

Burbleflop · 6 Feb 2006 at 15:48

That means that DNS and routing aren't a problem. When it goes **** up, what do you get if you telnet (start, run, cmd) to port 80 on a webserver? Ie, 'telnet www.jolt.co.uk 80'

Mark M · 6 Feb 2006 at 16:49

is there meant to be a space before the 80?

I tried both and got the following,

telnet www.jolt.co.uk 80

could not open connection to the host on port 80:connect failed

telnet www.jolt.co.uk80

could not open connection to the host on port 23: connect failed

tolien · 6 Feb 2006 at 16:50

Yeah, there's meant to be a space. Try telneting the router's IP, port 80 again (ie "telnet [router IP] 80")

Mark M · 6 Feb 2006 at 16:55

could not open connection to the host on port 80:connect failed

Any ideas what that means?

Mark M · 6 Feb 2006 at 16:58

When I do "telnet [router] 80" on my machine(working) it takes you to a blank screen that has "telnet [router ip]"

Burbleflop · 6 Feb 2006 at 17:04

Mark M said:
When I do "telnet [router] 80" on my machine(working) it takes you to a blank screen that has "telnet [router ip]"

That shows that the PC in question could open the web management interface of the router but the error on jolt shows that it can't open a http connection with jolt. My thought was that your web browsers (I saw that you tried more than one) were buggered.

I think your OS is borked, that's all I can think of. Any software firewalls on that machine?

Mark M · 6 Feb 2006 at 17:09

I couldnt telnet anything from the broken machine. The one that worked was on mine which is working.

No software firewalls other than the one that is built into the microsoft antispware but I only installed that after the problem occured.

Edit - would the browers being goosed stop outlook and 2 other programs from connecting to the net?

Burbleflop · 6 Feb 2006 at 17:48

Mark M said:
Edit - would the browers being goosed stop outlook and 2 other programs from connecting to the net?

Nope. Time to reinstall Windows I think.

Skilldibop · 7 Feb 2006 at 11:28

i agree.
you have network and probably transport layer connectivity, but not application layer connectivity. Seing as you've used integrated win32 apps (telnet) and 3rd party apps (firefox), it would seem there is a presentation layer issue. This can either be driver or OS. Though rehashing windows will mean re-installing the driver anyway so killing both birds with a big boulder. If it's just a standard install i'd go as far as trashing the disk and starting again. That will eliminate and virii that might be lurking that AVG might not have found, it's not infallable

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