Pin 11 on Arduino UNO doesn't work

Hi all,

I've been testing a Shield I've designed. On Pin #11 of the Arduino UNO there is a button. The button hasn't responded, so I tested everything until I've found that the problem is in the Arduino itself. So, most probably I've done somthing while testing which might have caused the problem. In order to avoid that on the future, I'd like to know under which circumstances such a problem can occur? The shield works ok, I've tested on breadboard and self-made pcbs, so it's not a problem of the schematics. It must be something I did.

Any idea is welcome!


could you re write code to use different pin or is it necessary? just a thought