Solve partition creation problems
If you have problems creating a Windows partition, check the following:
- Before you install Windows, the disk on your Mac must be a single partition, formatted as Mac OS Extended (Journaled). If the disk already has more than one partition, you must repartition it.
- The disk on your Mac must be an internal disk. You cannot use Boot Camp Assistant to install Windows on an external disk.
- If you have a Mac Pro with more than one internal disk and you want to install Boot Camp on a disk that isn’t in the first hard drive bay, remove the drives in the lower-numbered bays. You can reinstall the drives after you install Boot Camp.
- If a dialog appears in Boot Camp Assistant that says verification failed, try repairing the disk using Disk Utility (located in the Other folder in Launchpad), then opening Boot Camp Assistant again. If that doesn’t work, back up all the information on your Mac, then reinstall OS X. For more information about how to do these tasks, click your desktop’s background, choose Help > Help Center, then search for “repair disk” or “reinstall OS X.”