Sometimes after upgrading your Xcode and iPhone SDK installation you may see the alert “Base SDK missing” when you try to compile and build an old project (that was written with a previous version of Xcode and an older version of iPhone SDK). That issue is as easy to fix as performing some clicks. Let’s see how:
- Open old project. On the upper side of the Xcode window you should see the message of the missing SDK as shown in the image below.
- Click the info button (blue icon with the “i”).
- Navigate to the “General” tab.
- Under the “Base SDK for all configurations” choose the latest version of iOS (now its 4.1. Choose iOS Simulator if you want to run the program on your Mac, or iOS Device if you have a developer device and you want to build the project and run it straight to the device).
- Click “build and run” and your project should now compile as usual.