1. Did any msgs appear in the log?

2. try turning off iptables
and try logging in again. DO check the logfile /var/log/secure


3. how are the 2 machines connected: direct, via a switch, via a router, via a hub?

Hi Chris

Thanks for your help. It is working now. Appreciated your time.

here the problem does not seem to be on "linux" box. just for a moment, try
to disable the firewall on your "windows 7" machine.

then retry to connect.

Hello Friends

I just realized that I installed 'antivirus' software Norton in my window machine. That may be one of the reason I could not able to connect. Even I could not to connect to work after I installed this machine. Today I uninstalled this and tried. It is working perfect.

Thanks everyone for all you valuable inputs.
Highly appreciated.