You learn a lot after four months of working at a tech shop window.

Between October of 2012 and February of 2013, I was part of the University of California Berkeley's tech repair window staff. The Apple certifications had been earned, the time had been put in, and it was time to see if a geek who pretty much lived to tinker with Macs could help the university's 38,000-plus student body with whatever disasters happened--especially at the 11th hour with everything due at once.

The tech window is gone now (swept away as part of a mandatory building renovation and moved to a smaller store across the street), but over the course of more than 200 repairs for the wearied and panicked tides that crashed the tech shop window, I figured that there were three incredibly common Mac problems that you can easily fix yourself or at least limit the damage.

That clicking noise from your Mac is probably the hard drive, the most-used component in your computer with the most moving parts, so there's a higher likelihood that it's going to fail. But it's the one thing you don't want to fail, since it stores all the work you've done. So, we'd get the drive out of the computer, plug it into a USB or FireWire external casing, and then hook that unit up to a known-good Mac.

From there, we'd fire up a copy of Prosoft's Data Rescue 3 ($99; a demo is also available), select the bad hard drive, and run the Analyze test. This is the same software Apple uses sometimes at its Genius Bar to determine if your hard drive's about to take a nosedive. The program can be set to run a sigma-4 test that examines read and write functions across all areas of the hard drive. The test results are a good way to determine if it's time to replace your drive.

Not the easiest news to deliver to a frazzled student whose paper is due the next day, but if you can back up their data to a thumbdrive or catch a failing hard drive before it goes kaput, it will make things a lot easier in the long run and avoid a monstrously expensive bill from a data recovery center.

The lesson to be learned here: Invest in a few items that your computer will need to protect your data and back up. A trusty external hard drive can sync beautifully with OS X's Time Machine, keep you from losing everything, and in the event that something does go wrong, cleanly restore your data exactly the way you left it. At $99, Data Rescue 3 isn't the cheapest utility on the market, but it's one of the best applications around for cleaning up routine damage on your hard drive, recovering data from otherwise-deceased disks, and making sure your hard drive's still in good shape thanks to its Analyze test.

Thus, it never hurts to mow a few lawns, walk someone's dogs, or check the couch cushions for change to earn a few bucks and buy these items. Be prepared, and your data will thank you.

When good cables go bad

The 13-inch MacBook Pro notebook from mid-2011 is an outstanding computer, but some of these laptops apparently were made with a bad batch of hard drive cables that failed after about a year. Although something of a pain to diagnose (this one threw us for a few weeks until we saw a pattern forming), this proved to be an easy and fun fix.

If a MacBook Pro seemed unable to boot, find its operating system, or appeared sporadic in reading and writing to its hard drive, it became standard practice to take the hard drive out of the computer, put it in an external casing, then run Data Rescue 3 on it. If the drive came up clean, the hard drive cable was the most likely culprit.

If a known-good hard drive was swapped in and the MacBook Pro exhibited the same issues, then the hard drive cable became a definite suspect and an order was placed for a replacement cable (available on eBay for about $25 or from iFixit, which has an online installation guide, for $50).

The fix took about ten minutes: We opened the MacBook Pro, removed the old cable, installed the new replacement cable, inserted the old hard drive, closed up the computer, and made sure everything was good to go. Yes, students had panic attacks as no one wants to learn that their MacBook Pro suddenly can't read their hard drive, but for a relatively cheap fix that could be finished minutes after the replacement part arrived, there are worse things that can go wrong with your MacBook Pro.

When you have a problem connecting to an external device (hard drive, printer, etc.), always check the cabling. It helps to have spare USB or FireWire cables around, and while you may not have a spare Thunderbolt cable (they're expensive) or an extra display cable, you can borrow one from a friend to diagnose the problem.

The same logic applies to your Apple laptop's internal hard drive. If you find your laptop is having trouble accessing your hard drive, are feeling brave of heart, and have access to a set of Phillips head screwdrivers and a known-good hard drive cable (say, from a friend who has the same laptop), try swapping the good hard drive cable into your laptop and test from there. If you don't feel like opening multiple computers and poking around, bring your laptop to an Apple Store's Genius Bar or Apple Authorized Service Provider in your area, and they should be able to resolve the problem quickly and without too much fuss.

The thrill of the spill

As good as the intentions of the UC Berkeley student body may have been, accidents did happen and sometimes they involved various fluids spilling into their otherwise-beloved MacBooks and damaging the logic board. In one instance, we never did get an explanation as to how a bottle of shampoo exploded inside a backpack and took most of a MacBook Pro down with it. In the end, we simply dubbed that machine the "Shamputer" and its tale became both a legend and a warning.

If you believe you've spilled anything (water, soda, trendy energy drink, etc.) on your Apple notebook, shut it down immediately, lest you continue short-circuiting your computer and thus blasting small holes through its components. Just because your computer works for a while after you've spilled liquid on it doesn't mean you're in the clear. Damage from liquid spills start out small and difficult to diagnose, and then over time spreads to become larger functional issues.

The best thing to do in this case is to take your Mac to an Apple-authorized service center. But if you are feeling handy and are OK with voiding your AppleCare warranty, you can clean your computer yourself. Unplug it, open it up, and disconnect the battery and all connections to the logic board. Then sit the open computer by a fan while gently scrubbing all sections of the logic board with cotton swabs and isopropyl alcohol. Clean both the top and bottom of the logic board if possible, then let the exposed MacBook dry in the path of the fan overnight before piecing everything back together and turning the computer back on. With any luck, the crisis will be over.

Take care

The tech shop window is gone, and the undergrads need to become better at lying about what happened to their computers (hint: if the scent of Pabst Blue Ribbon wafts from the inside of a MacBook Pro that won't turn on, it probably didn't break on its own), but the main lesson remains: Take care of your Mac and it'll take care of you.

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