Statistically speaking, starting up from cold is the time when your Mac is at the greatest risk of suffering a problem.
In many cases, it will be software rather than hardware that causes any strange behaviour, which is the lesser evil since it's usually easier to fix.
Failure to boot up reliably can be symptomatic of something more serious, but much more common problems are slow boot times and slow logins. Let's look at these in turn.
Your Mac loads an awful lot of code before it gets to the Finder view you're used to seeing, and the longer you've had the Mac, the greater the chances that there's a lot of legacy stuff hanging around which can slow down the startup process.
A "vanilla" or completely fresh system will generally start up quickly on any modern Mac, but as you install programs over the years and fill up your boot drive, the computer has to perform more disk activity and sift through more startup items, even unused ones, before it can finish booting.
One remedy for this is to use an uninstaller program like AppZapper or AppDelete to delete any unused apps on your system, including all associated support and library files. You can trash the application's folder, but this by itself won't get rid of other resources placed elsewhere in the system when it was installed.
If you go to Macintosh HD > Library > StartupItems you will see the user-installed things that your Mac is loading as it boots. Typically, these are services that applications or peripherals need to run properly such as printers, scanners or dongle security enablers.
It's possible to delete items from this folder, but be careful that you don't trash anything that you actually need. If you are absolutely sure that you can go ahead – for example, if you find resource files for a printer that you no longer use – removing them can help improve boot times.
This folder is part of the system and is read before anyone logs in, so changing its contents will affect all user accounts. In addition, keeping your boot drive relatively clear by offloading media files and large iTunes libraries onto secondary drives will help overall performance.
Slow logins are another potential problem and are solved in a similar way to that just mentioned. In this case the offending items are likely to be located in the System Preferences > Accounts > Login Items section.
When you install some peripherals like scanners or printers, or if you ever choose to allow an application to open at login, these things will appear in this list. Each one must be loaded by the system, which takes time.
If you select any unwanted items and hit the minus button to remove them you should notice an improvement in login speed.
Nuts and bolts
If your Mac exhibits startup problems following a system update, you may have to boot from the OS X install DVD and run disk repair on the boot drive, then try a restart.
If you are running OS X 10.5 and regularly back up using Time Machine, it should also be possible to roll back the system to its pre-updated state by booting from a system disc, connecting the backup drive and choosing Restore System from Time Machine. This will replace the corrupted system with a working one, though it's something of a last resort.
Before you have to do that, though, or if you are not using Time Machine as your backup choice, there are a few other tricks to try to fix startup problems. Holding down Ctrl+Alt+[P]+[R] at startup until you hear the startup chime twice will reset the Mac's PRAM, which sometimes clears out strange glitches.
On a PowerPC-based Mac like a G4 or G5, you can hold down Ctrl+Alt+[O]+[F] to boot into Open Firmware. Then, if you type reset-nvram followed by reset-all your firmware will be reset and the Mac will reboot, which can deal with some otherwise unexplained booting or stability issues.
There's no easy way to access an Intel Mac's version of open firmware, which is known as EFI, but on all OS X systems you can boot straight into the UNIX heart of your system, bypassing the normal startup procedure in an attempt to solve startup problems.
Be aware that as well as helping, you can unwittingly do great harm to your system from the command line, so if you're brave enough to enter this world, stick to the exact commands.
If you hold Ctrl+[V] during startup you will enter Verbose Mode, which uses text to display what is being loaded during startup. This can help you to identify the point at which a fault may be occurring by seeing where the startup fails. By holding Ctrl+[S] during startup you enter Single User Mode. Here you can run deep level disk checking.
At the command prompt, type /sbin/fsck –fy and the system will check the drive thoroughly, which may take a while. If any errors are found, repeat the command to run the check a second or even third time until it stops reporting problems. At that point, type reboot and press [Enter] and see if that has solved the problem.
A further option, if none of the above methods work for you, is to perform an archive and install procedure. Boot from the OS X install DVD, choose to install OS X and then choose the Archive and Install installation type. This will install a fresh system and 'quarantine' the old one without deleting it.
If you think some element of the system software may be the problem, you can check the box marked preserve users and network settings and this will import your Home folder and personal data and settings. The trick then, if the new system works, is to bring it back up to date without repeating the step that caused the problem in the first place.
As an aside, when major system updates are released it's often advisable to wait at least a few days before installing them and watch for reports on the web to see if they exhibit problems. This way you can save yourself some potential headaches.
How to manage login and startup items
1. Go to your boot drive, Macintosh HD, then navigate to Library > StartupItems. You will see the items your Mac loads during its initial startup phase associated with third-party apps. Since we no longer need the interface driver, it can be deleted, which will speed up booting a little.
2. Go to System Preferences > Accounts > Login Items. Here you can see what is set to load when you log in. It could be that when you installed peripherals like printers, scanners or gaming devices they placed code or applications in here. If you know you no longer need a particular device, you can remove its associated login items.
3. To choose a different startup drive, go to System Preferences > Startup Disk and choose from available local volumes including bootable CDs or DVDs and a Boot Camp partition if there is one. Or, when starting up, hold down [C] to boot from CD/DVD or hold down Alt to bring up the volume selection screen.
First published in MacFormat, Issue 204
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