XP Network problem (which is driving me crazy!!)

[Geraint]

I have a weird XP network problem. I have two XP
machines connected via a crossover cable.

Both machines can ping their own IP addresses but cannot
ping each other's (so TCP/IP is installed and is working
properly on each machine). Neither machine has any
firewall software running on them (inc. the XP firewall -
I've disabled this on each network connection on each
machine).

When I boot up machine one it's as if the it's network
card isn't active as it doesn't send or receive any
network packets (to broadcast it's existence). When I
boot up machine two it alway's send's network packets
(1,275 bytes to be precise).

Also, machine two's network card always detects when I
reboot machine one as a message pops up stating that the
network cable has been disconnected, and then states that
it has been reconnected when machine one comes back to
life. Machine one never does this - there are no
messages displayed by machine one when I reboot machine
two.

I haven't used my network for a while but I kind of
remember everything working properly before I ran the
Microsoft Baseline Security Analyzer about 4 or 5 months
ago. So I kind of think this is definitely something to
do with the security of the network on machine one.

Does anybody have any ideas?? This is driving me crazy -
I really don't want to have to reinstall XP for a fourth
time.

Thanks in advance for your time and help.

Geraint.

 

[Kevin]

The last time I ran the Security Analyzer, it just made recommendations, it
didn't change anything. Is there a possibility you've changed something.

Do you get a link light on Machine 1? What about the NIC status in the
Device Manager? Is the NIC device operating properly?

 

[Geraint]

Hi - I probably did change something as I always download
the latest security patches and make the recommended
security changes.

I do get a link light on machine 1 and the status of the
NIC is listed as functioning properly. The crossover
cable and NIC work on a different PC without a problem.

I've done something stupid but cannot remember what
(although changing one setting in the registry springs to
mind). Is there a tool out there which can reset all the
network settings back to how they were after an initial
install of XP?

Thanks again.