Setting up used computers

At MacFixIt and on various Apple-related discussion and support forums, many people mention problems and odd behavior they get from recently purchased used computers. Someone will buy a computer on eBay and be irritated that they cannot change a short username from "Joe Smith" to whatever they want, or there might be some program that keeps popping up warning messages or even general slowdowns that weren't apparent when they first bought it.

Apple discussion poster "turfcat" writes:

"I purchased a used computer and thought I had managed to change the user over to me,. However recently during a shutdown under low battery, when the computer was turned on again voila, the old user was front and center on the finder menu."

Used computers can be cheap, and many times, you can get a great deal on one; however, assuming the hardware is working properly there are some basic recommendations we have to avoid irritating problems. These will not only keep your computer running fine, but they will also ensure you are being as safe as possible with your personal information.

1. Ensure you have support disks

All Macintosh computers come with a couple of support disks that contain the operating system and diagnostic utilities, along with optional installation files. Be sure the seller includes these disks in the sale, as those are licensed for that computer. If for some reason the seller has lost the disks, be sure to get a retail copy of the operating system. Unfortunately, the retail version does not have specific hardware testing software, and while you can get that from Apple, some people have reported it being very difficult to do so. You can get by without hardware and diagnostics, but since most problems are software based, you will benefit from having an operating system installation disk around.

2. Format! Format! Format!

Unless you have a very specific reason for keeping the previous owner's data and applications, get rid of them and start over. Treat your computer like a house or office, and set it up from scratch when you move in. You wouldn't want to have someone else's piles of junk around in your house, so do the safe thing for your computer and wipe everything clean off the disk. Boot off the support disk and use Disk Utility to both repartition and format the drive. Then run the Mac OS X installer and give yourself a fresh installation. Even though there isn't much malicious software for OS X, who knows what has been done to the system and it's best to clear it and start over.

3. Reset the PRAM and SMC.

Who knows what settings people have put into the computer, and many times faulty PRAM or System Management Controller settings can have the computer behaving oddly. Resetting the system management controller can be different for various Mac models, but usually it involves shutting down and holding the power button for a few seconds; however, look up the exact method for doing this on your system at Apple's support site (http://www.apple.com/support). The following are some pages for how to do this on several Mac models:

One thing to keep in mind is that some people might have locked their firmware, which would prevent you from booting off the installation disks or resetting the PRAM settings. To test for firmware passwords, restart the computer and hold the options key. This should bring up a boot menu, but if the firmware is locked, you will be prompted for a password. If this happens, you can reset the password by temporarily changing the amount of RAM the computer has. Doing this can be different for every computer, so unless you know how, we recommend you have this be done at an authorized Apple service center.

What if part of the deal was all the software on the computer?

These types of situations can be complicated, but unless the seller gives you the original disks and license (numbers and agreements) for the software on the computer, then they still technically own the software. Most packages are licensed for installation on one computer at a time by the holder of the license, so unless the seller has given you that license, don't expect the company to offer you any support for the software. This includes the agreement, serial numbers, and installation disks.

If you have all the software installation disks, formatting and reinstalling is recommended. However, if you feel that formatting is not what you want, at least set up a new account for yourself. This is the bare minimum of what you should do with a used computer since it will prevent any odd settings from running (cookies, preferences, application support files, cached items, and so on). To do this, login to the current administrator account and create a new administrator account in the "Accounts" system preferences. Give it whatever name and password you want and then log out and log into the new account. Finally, go to the "Accounts" system preferences again and delete the old administrative account. While you can choose to save the old user's data and settings, it is not necessary to do so.

Comments or Questions? http://www.macfixit.com/contact

Resources