Why wifi automatic connection not work?

I have set the wifi auto connect to router but every time when it boot up I have to click connect in wicd manually.

Another problem is that if I don't use wifi for a period, such as I didn't browse web page for 10 min, the wifi will disconnect. I have to keep ping some ip to make wifi alive. What is this problem?

What exactly did you do to connect auto?.Did you manage to alter the interfaces file?..One thing is to start the interface and another one to initiate the wicd...