Xcode 4 - “Archive” is greyed out?

Question

I would like to archive my application, but the Archive option is greyed out. What could cause this?

Answer 1

As the other answers state, you need to select an active scheme to something that is not a simulator, i.e. a device that's connected to your mac.

If you have no device connected to the mac then selecting "Generic IOS Device" works also.