127.0.0.1

Use the command
route add 127.0.0.1 which should include an entry in the routing table that tells IP that it may use this interface as a route to destination 127.0.0.1

Issue the Ping command and it should be able to Ping. Let us know.

When I "route add 127.0.0.1", I get: "SIOCADDRT: No such device"

Use ifconfig lo 127.0.0.1 and that should activate the loop back interface.
Post the output of /sbin/ifconfig.
Use route add 127.0.0.1 and see if you still get the same error.

have u install TCP/IP in ur PC???l