When we first start Wicd on backtrack it will show u error message like this.

then i found out the solution on backtrack Wiki.

1. Reboot your computer.
2. Before starting your Wicd, enter these shell commands
root@bt:~# dpkg-reconfigure wicd
root@bt:~# update-rc.d wicd defaults

now you will not see any error notification appear next time u start Wicd.