Base SDK Missing?

I finally got the new version of Xco开发者_运维知识库de and the iOS4 downloaded and was finally going to attempt to put my first app onto a device. I was going through the provisioning profile and got to the point where I needed to open Xcode - then all it says in the "Device" pulldown is "Base SDK Missing".

If I go to "Project > Set Active SDK" all I see are grayed out letters saying "Base SDK Missing."

Click the name of your app in the Targets menu, then click on the blue "info" icon at the top. In the "build" tab, look for the "architecture" heading and change "Base SDK" to iPhone Device 4.0"