1. Open Terminal
2. Execute this command
   defaults write com.apple.desktopservices DSDontWriteNetworkStores true
3. Either restart the computer or log out and back in to the user account

If you want to prevent .DS_Store file creation for other users on the same computer, log in to each user account and perform the steps above—or distribute a copy of the newly modified com.apple.desktopservices.plist file to the ~/Library/Preferences folder of other user accounts.

Make it a point to check for Apple software updates once a month to keep your system running optimally. From the Apple menu, choose Software Update while your computer is connected to the Internet. Software Update will assess the Apple software on your computer and check our servers for new versions. If it finds any, the updates will appear in the Software Update window. Select the checkbox for the software you want and then click the Install button to download and install the software. You can configure Software Update to automatically check for updates either daily, weekly, or monthly.

Put Your Files Away

Put your files away where you can easily find them. This can help prevent accidental file deletion and help you find things much more efficiently. You can get organized by creating new folders (in the Finder, press Shift-Command-N) and arranging them into a workable hierarchy for your files at hand, or you can move your files into existing folders.

Name Your Files

Go through your generically-named files and folders and give them more descriptive names so you can find what you need fast. This can help you get organized and makes it easier for Spotlight to search and find what you’re looking for, especially one file amongst your digital photo collection with names like DSC_0431.jpg and so on.

Note: If you use iPhoto to manage your photos, don’t use the Finder to rename the files.

To reduce the amount of clutter on your hard drive, free up some disk space by archiving large, seldom used files (learn how here), and be sure to name the resulting archive file appropriately too, so you know what’s in it. Delete any unnecessary or outdated personal files whenever possible and anything that you no longer want or need—just drag them all into the Trash and don’t forget to empty it.

Back Up Your Files

To prevent losing your prized or important files, make it a point to back up on a regular basis. You can back up files onto a CD, DVD, external hard drive, iPod, iDisk, or other storage medium and then delete the copies on your hard drive to free up some space. To learn how to back up files, choose Mac Help from the Help menu in the Finder and do a search for “back up files.”

Check for Viruses

Macs are far more less likely to get a computer virus like Windows PCs are prone to but that doesn’t mean it’s impossible. If you don’t already have antivirus software, you may want to consider making a purchase. If you have the software installed, be sure to keep your virus definitions up to date—you can find the latest updates on your software manufacturer’s website.

Clean the Outside

Dust and other debris can harm your computer’s innards if you allow the stuff to build up around your workspace. Use a soft, dry, lint-free cloth, feather duster, or canned air to clean your Mac’s outside as well as the surface areas around it. You can use a slightly water-dampened cloth to clean the screen. Do not use any type of liquid cleaner to clean your Mac.

• Reopening an application after it unexpectedly quits
• Mail may reset to default if it unexpectedly quits twice in row

This file is where all the account settings are stored. As a result, all the non-.Mac account settings are lost. If you have a .Mac account, that account would appear to have been preserved because Mail would set it up automatically using the System Preferences > .Mac/MobileMe settings.

You may want to make a backup copy of the ~/Library/Mail folder first (e.g. by dragging it to the Desktop while holding the Option (Alt) key down), just in case something else goes wrong while trying to solve the problem. This is where Mail stores the mail on your computer.

Now, there are at least three ways to restore the account settings:

1. Restore ~/Library/Preferences/com.apple.mail.plist from a backup if you have one. Mail shouldn’t be running while you do this.
2. Set up your mail accounts again (you may want to quit Mail and trash the new com.apple.mail.plist first to start over). If given the option to import existing mailboxes or something like that, don’t. Just enter the account information and Mail will automagically rediscover the data in ~/Library/Mail/ when done. You’ll also have to re-configure some of the Mail > Preferences settings. For spam-related security reasons, the first thing you should do is go to Preferences > Viewing and disable Display remote images in HTML messages if it’s enabled.
3. Mail may have renamed the old preferences file to com.apple.mail.plist.saved. If that’s the case, you may try trashing the newcom.apple.mail.plist and renaming the old com.apple.mail.plist.saved back to com.apple.mail.plist. Again, be sure Mail isn’t running while doing this. Given the circumstances, there exists the possibility that com.apple.mail.plist.saved became corrupt, but that often is not the case and the settings can usually be restored by just renaming the file back to com.apple.mail.plist.

As a side effect of re-creating com.apple.mail.plist, Mail might rename Outbox (which is where messages waiting to be sent are stored) toDelivered. The name of that mailbox is actually a misnomer, as it would contain messages (if any) that couldn’t be delivered for some reason. You can delete that mailbox if you wish.

Note: For those not familiarized with the ~/ notation, it refers to the user’s home folder. That is, ~/Library is the Library folder within the user’s home folder, i.e./Users/username/Library.