Cannot ping or be pinged no matter what...

[Brian Foster]

I've been managing networks for over five years, but I've come across
something that's got me baffled.

I have a Windows XP machine (SP2) on a workgroup network of 4
computers. This one computer cannot ping anything else (including the
default gateway), and cannot be pinged from any other machine on the
network. This causes problems for applications I run on the machine
that rely on ICMP to test for the presence of particular machines. But
the wierd thing is that except for pinging, XP's device manager
reports the network card functioning correctly, the machine in
question has full internet connectivity, and it can be found if you
put its name or IP address directly into a run box e.g.
\\192.168.1.101\c$

Some more info:

On the machine in question Ping itself works, because the machine can
ping 127.0.0.1 and it's own IP address but cannot see the gateway
192.168.1.1 to which it is connected by Ethernet (a Linksys WRT54g).

I've confirmed it's not the cabling or the router setup, because
connecting another machine to the same ethernet cable and hub port
works, and when I do that, the new machine connected by the same cable
can indeed ping the router and other machines.

All wireless machines on the network can also ping the router via
Wireless. So it's just this one computer that's driving me nuts.

Here's what I've tried:

* Releasing and getting a new IP address from the router (a DHCP
server). No effect.
* Forcing a manual IP address. No effect.
* Changing the ethernet cable. No effect.
* Changing the network card, to one that's been known to work on the
same network. No effect.
* Reinstalling the network card drivers.
* Opening firstly the ICMP and then all ports on the machine's SP2
firewall, and then even including disabling the entire firewall. No
effect.
* Running a netsh int reset to reset the protocol. No effect.
* Turning off the router's firewall. No effect.

Any ideas? Am I looking at reinstalling the TCPIP files off the SP2
CD? Or a full reinstall? Suggestions welcomed!

 

[brianfos]

It's still happening after a reapplication of SP2, which is even more
frustrating. I've double checked the addressing and subnet mask details
given out by the DHCP server, and checked there are no rogue LMHOSTS
entries that could be causing a problem. I've also cleared the ARP
cache just in case.

I've changed the cables and ports on the router too, to no effect.
Other machines can ping it fine, this one cannot.

A Ping just continues to report "Destination host unreachable" when
done from the machine in questoin, and pings to the machine from one of
the working machines, or the router's software just return "Request
timed out" messages. A tracert stops at the default gateway.

I've checked that nobody had installed zone alarm of third party
firewall programs on here, and checked the add/remove programs list,
event viewer and system32 file to make sure there are no wierd looking
programs, dlls or tcp messages (in the case of the log).

My latest lead has come from running a packet sniff using etheral,
where I found that no packets are actually transmitted through the card
when I run a ping on the default gateway, only STP packets go across
the network from the router when there is no network activity. Not sure
where this is going to take me, I am going to run the trace on one of
the working computers next to see if I can get more info that way.

ALl ideas in the meantime are welcomed!

B

 

[Guest]

I have gone thru that same thing in the past on the same network...it was the
cable...95% of the systems had no problem with it...the other 5% would not
work. I have also had ethernet cards that tested fine and did not work,
switching tham out was the fix.

 

[brianfos]

I have thoroughly gone through every service and IP setting and can't
determine what it is, but i have discovered that everything works
perfectly in Safe Mode with Networking.

That means I now have the task of examining every startup application
and service to determine where the problem is.

Life was so much easier as a paperboy.............