XP and 2K computer can't ping nor see each other

[Crazy Cat]

I've got a six computer network, one XP pro, one XP home, 2 linux, and 2
W2K computers -- all the computers are connected to a Linksys Wireless/LAN
router and a cable modem (only one computer is wirelessly connected - the
others are connected by ethernet). After installing several Windows XP
security updates from yesterday (at least that's pretty much the last thing
I remember doing before these problems started), while all the computers
can get to the internet, Win2K computer 1 can ping Win2K computer 2, but
Win2K computer 2 cannot ping Win2K computer 1. Win2K computer 1 also cannot
ping Win XP pro and the WinXP Pro machine cannot ping it. All the other
computers (an XP pro and two linux computers) are totally accessible.

Any ideas?

Thanks,

Crazy

 

[Crazy Cat]

I've got a six computer network, one XP pro, one XP home, 2 linux, and
2 W2K computers -- all the computers are connected to a Linksys
Wireless/LAN router and a cable modem (only one computer is wirelessly
connected - the others are connected by ethernet). After installing
several Windows XP security updates from yesterday (at least that's
pretty much the last thing I remember doing before these problems
started), while all the computers can get to the internet, Win2K
computer 1 can ping Win2K computer 2, but Win2K computer 2 cannot ping
Win2K computer 1. Win2K computer 1 also cannot ping Win XP pro and the
WinXP Pro machine cannot ping it. All the other computers (an XP pro
and two linux computers) are totally accessible.

Any ideas?

Thanks,

Crazy

Found the answer to my own question --- I had changed the MAC address of
the NIC on my to match the NIC that my computer had originally been
provisioned with for the cable modem. Looks like everything went to hell
after that -- though I don't know why the problem was restricted to
only a couple of computers.

Crazy