The purpose of a spare account is to have a pristine set of user files, extensions, and preferences to load at startup. This can often get your Mac running if your main user account is having problems, either at startup or while you’re using your Mac. Once your Mac is up and running, use a variety of methods to diagnose and repair the problem. You must create the account before trouble strikes, though, so be sure to put this task at the top of your to-do list. When you’re having startup problems, Safe Boot can help you get your Mac up and running again. Solve some startup issues by giving the PRAM/NVRAM a kick in the pants. This guide will show you how. In some cases, a Mac that won’t finish starting up, or starts up and then freezes, may need its SMC reset. If your Mac gets stuck at the gray screen, you have a bit of detective work ahead of you. Unlike the blue screen problem (mentioned below), which is straightforward, there are a number of culprits that can cause your Mac to get stuck at the gray screen. It may be easier than you think to get your Mac running again, although it may also take a bit of time. This guide will take you through the process of diagnosing the problem’s cause. It may also help you perform the repairs needed to get your Mac up and running again. This guide shows you tricks to get your Mac up and running, so you can repair the drive with Apple or third-party software. We don’t limit the solutions to only one method of getting your Mac to boot. We also cover methods that could help you get your Mac running to the point where you could repair the startup drive or further diagnose the problem. Trying again with the same upgrade install is unlikely to work because upgrade versions of the OS don’t include all the necessary system files, only the ones that are different from the previous version of the OS. Because there’s no way of knowing which system files may have been affected by a corrupt install, the best thing to do is to use an update that contains all necessary system files. Apple provides this in the form of a combo update. This guide will show you how to obtain and install combo updates.
