[Q] problem in installing cwm[recovery] in galaxy duos topic

Hello, it would be a great help if u help in resolving it
[samsung galaxy duos ]
in odin after selecting auto reboot and f.reset time and selecting cwm recovery in pda the process is being failed...even after disconnecting and again trying it with different usb cables it is getting failed. i have also installed usb drivers. how can i install cwm recovery and root my device.