LAN network-Unable to ping between machines

HardwareTwitch

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Aug 18, 2012
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2 machines 1 running xp other windows 7.

ping from windows 7 to xp with lan ip does not work.
(ping 192.168.1.100--UNBALE to connect fails)
where as ping from xp to windows 7 with its lan ip works.
(ping 192.168.1.101--connects and successfully pings)

so what is the problem here 1 machine can ping other whereas other can't ping back on same network.

Pls guide me on this , thanks.