We left off last week with the question: “why would I need to disable my anti-virus software when installing new applications on a Mac running OS X?” You’ll remember my flippant answer: “what’s a virus? Oh, yeah, they have those on Windows”

The truth is, you don’t need anti-virus software on a Mac running OS X. There have been – count ‘em - zero, zilch, none, nada, viruses out there in the wild that can affect the operation of your Mac. Why? It’s partly due to the relatively small numbers of Mac users versus Windows users. If you’re building up your ego by causing misery for others, you’ll get a bigger boost by frustrating hundred of millions rather than tens of millions. It’s also due to Apple’s aggressive security update strategy, and the inherent security, at the code level, of the UNIX environment (which Mac OS X is built upon).

But, if you do choose to use an anti-virus application on your Mac, why would you have to turn it off for the time it takes to install new software? Because modern worms, viruses, and other forms of malware get deep into a computer system by installing themselves as if they were “legitimate” programs.

One of the ways that anti-virus applications do their jobs is to monitor your computer for attempts to install software, then prevent them. Obviously, if you don’t turn it off, the anti-virus application may well try to prevent your installation of legitimate software.

Next question. “Dear MacMaineiac. What can I do, on a regular basis, to keep my Mac OS X system running at full efficiency?” Another great question! Here’s what I recommend. If you find yourself unable to open a particular file, or if your Mac is running slower than usual, open up Disk Utility (Applications – Utilities – Disk Utility), click on the icon for your hard disk, and click the button labeled “Repair Permissions”. Disk Utility will then check that all your files have the correct user permissions (it’s a complex UNIX thing – just trust me – you need correct permissions). When the process is complete, quit Disk Utility and Restart your Mac. It’s also a good idea to Repair Permissions after you install a new application, or an update to an application, or allow an automatic update through Software Update.

© 2004 Peter F. Zimowski