Use OS X Combo Updates to Correct Installation Problems
Apple routinely releases updates to OS X that are available through the Software Update process or the Mac App Store, depending on the version of OS X you are using. These software updates, available from the Apple menu, usually provide the simplest method for ensuring your Mac’s operating system is kept up to date. They can also cause problems, particularly if your Mac should freeze, lose power, or otherwise prevent the update from completing. When this occurs, you end up with a corrupt system update, which may manifest itself as simple instability: occasional freezes or the system or applications locking up. In the worst-case scenario, you may have problems booting, forcing you to consider reinstalling the OS.
Another problem is related to OS X’s incremental approach to updates. Since Software Update only downloads and installs system files that need to be updated, you can end up with some files being out of date with respect to other system files. This can result in infrequent system or application freezes, or the inability of an application to launch.
Although the Software Update problem is infrequent, and most Mac users will never see it, if you’re having some unexplained issues with your Mac, the Software Update problem could be the culprit. Eliminating it as a possibility is very easy to do.


