When your icons get messed up, or you just feel like doing some good old fashioned maintenance, rebuilding the desktop is the way to go. However doing so in Mac OS X isn't nearly as simple as it used to be. Now you will have to find three files in the Preferences folder of your home directory's Library folder. These three files are LSSchemes, LSClaimedTypes, and LSApplications. Once you find them, throw them in the trash, log out, and log back in. Extra Tip: Rebuilding the desktop file under Mac OS 9 (not Classic) can actually help alleviate problems in Mac OS X as well.

This isn't so much a troubleshooting tip, as it is some very good advice. An improper shut down in the previous versions of the Mac OS, normally didn't affect too much. But with Mac OS X, an improper shut down can really do some damage (do to the Unix underpinnings, which isn't meant to even be shut down). If you haven't already, this might be a good time to invest in an UPS (battery backup) system.

Like all other OS's, corrupted hard drives can give you a lot of trouble. Making sure your drive is in tip top condition prevents 90% of all problems you can have with computers. Luckily, Unix has a nice command to help you repair your disks. To use it, you will have to start up in Single User Mode (by holding down Command+S during startup), until you get a text prompt. Here, you type in "/sbin/fsck -y" repeatedly until you get a message saying "The volume appears to be OK." Once that happens, type reboot to restart your Mac. Alternatively, you could start up using the Mac OS X CD, and using the Installer to run the Open Disk Utility from the Installer menu.

There are now a couple third party disk utilities that are compatible with OS X. Micromat's Drive 10, Norton Utilities, Norton Systemworks, and Alsoft Disk Warrior are all able to handle Mac OS X files. When fsck isnt enough, use one of these utilties.

While we would like to avoid using Classic whenever possible, that's not entirely possible, yet. So, just like in older version of the Mac OS, Trimming the extensions is a very good way to eliminate conflicts, keep errors to a minimum, and speed things up (something Classic really needs). This means that our years of experience with older Mac OS's will come in handy here.

Mac OS X does have some quirks sometimes such as graphical artifacts, things not showing up, or changes not being applied. If you have made sure you did everything right, log out and log back in via the Apple menu. This is nearly identical to restarting, except it is MUCH faster. Then, retry what you were having problems with, to see if it works now.

Mac OS X is very new, and therefore is not optimized, is missing features, and still has bugs lurking about. But, Apple is working very hard on fixing these things, and as soon as an update is available, you should grab it. This goes for applications too. Developers really haven't had time to put much effort into their OS X ports/projects yet, so updates will be nessecary. If not, a restart is probably needed.

Remember how force quitting applications in the classic Mac OS would usually not work, and 9 times out of 10 bring the entire system down? That has all changed with OS X. Because of Unix's protected memory, usiing command+option+escape now brings up a window, with a list of applications to force quit (including the finder). Once you do a force quit, you are free to work on anything you wish, including launching that application again, and starting over with it. No longer is Force Quitting a lesson in futility.

If your computer seems to be running sluggishly, it may be the fault of only one application. To find out which application is causing your machine to crawl, you can either open the included Process Viewer utility, or open the Terminal and type 'top'. I recommend using the Terminal as it tells you the names of the applications, rather than cryptic names. From there, you can decide to kill the application, reinstall it, or whatever you need to do to get it working again.

With Mac OS X comes Unix-like file permissions. Sometimes, your computer won't let you do something because you don't have enough privileges, even though you may be the only user. In that case, you need a Super User (called root). To enable root, you will need to open the NetInfo Manager, use the directory browser to locate your user name (under /users/). Then, you select your name, click the little lock on the bottom to make changes, and finally use the Domain menu to find Enable Root User (in Security). It will prompt you to enter a root password. Now, you can log in with that root and have permission to change anything.

Various system settings are stored in this RAM, and they can become corrupted from time to time. If you are experiencing strange problems, try resetting the PRAM by holding down the command+option+P+R keys while starting up. Keep holding down the keys until your hear the startup chime two times. Let go of the keys, and the computer will continue to start up.

Another type of RAM that stores obscure settings (most notably firmware), is the NVRAM. Again, if this becomes corrupted, very odd problems could crop up with your Mac. To reset the NVRAM, holding down the command+option+O+F keys while starting up. This will start you up into Open Firmware, where you can enter commands into the prompt. Enter the folling commanrds to reset the NVRAM and restart your Mac:

1. reset-nvram (hit return)
2. reset-all (hit return)

The Power Management Unit controls various I/O aspects of Apple laptops. If the PMU is corrupt, a wide variety of problems can occur. To reset the PMU, follow the directions on the Apple Knowledge Base.

Similar to the PMU for laptops, desktops Macs have a microcontroller that handles many I/O functions. Again, if this becomes corrupt, strange happenings can occur. To reset the CUDA switch, you will have to open your Mac, and look around on the motherboard for a white button (many times it is near the RAM slots). Press this button once (only once) to reset the CUDA.

• Command + S=Single User Mode
• Command + V=Verbose Mode (watch the Start-up status)
• Option=Volume List (A.K.A Startup Disk)
• Command + Option + P + R=Reset PRAM
• Command + Option + O + F=Start into Open Firmware

• MacFixIt
• Micromat (Makers of Drive 10)
• Symantec (Makers of Norton SystemWorks)
• Alsoft (Makers of Disk Warrior)