Expert solutions for misbehaving Macs

Network issues

If you are having networking problems, a reboot will often force a Mac to look again at what network interfaces are connected. Sometimes, an Ethernet cable may not be recognised, and even going into System Preferences > Network and configuring it may not help. A log out or restart almost always fixes this.

If a problem persists, reset the PRAM. If your AirPort connection isn't picked up, try switching AirPort off and on again, which forces a re-scan. Make sure you know the password for any protected networks you're trying to join.

A weak AirPort signal may be the result of thick walls or too great a distance from the base station, in which case a booster antenna or a second, relay base station can help.

If you have several Macs but some are not showing up under the Network or Shared Places tabs in Finder, go to System Preferences > Sharing on the relevant Macs and make sure that Personal File Sharing is switched on.

How to verify and maintain your system with OnyX

1. Download and install OnyX, then fire it up. It's recommended to back up before performing any maintenance. In the Verify tab, you can make OnyX check the structure and reliability status of your startup volume, which is recommended every once in a while to catch any problems before they become serious.

2. In Maintenance > Rebuild, you have the option to rebuild the Spotlight index, which is helpful if you are having problems with Spotlight. If you have been having problems opening files, try rebuilding the LaunchServices database from this menu, as it often corrects problems between files and their helper apps.

3.In the Automation section, you can repair permissions and clean out the various system and user caches, which can speed up the computer and deal with inexplicable application crashes or launch problems, and problems with Software Update. After performing these tasks you will need to restart the Mac.


First published in MacFormat, Issue 204

Now read Quick fixes for 10 common Mac problems

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