Q&A: MacFixIt Answers

MacFixIt Answers is a feature in which I answer Mac-related questions e-mailed in by our readers.

This week, readers wrote in asking about the inability to format a drive due to "partition map" errors, how to determine what is using up space rapidly on the hard drive, how to restore a missing Safari program, and the options for tackling an iMac that continually shuts off in the middle of use. I welcome contributions from readers, so if you have any suggestions or alternative approaches to these problems, please post them in the comments!

Question: Unable to format a drive due to partition map errors
MacFixIt reader Leslie asks:

Mountain Lion volume erase is failing with an error that it could not modify partition map. Is there a way around this?

Answer:
Instead of erasing the volume, try repartitioning the drive by selecting the drive device in Disk Utility (this is the item directly above the list of volume names on the device), and then use the Partition tab that appears to set "1 Partition" from the drop-down menu. Click the Options button and be sure the "GUID" partition type is set, and then click the Apply button. This should set the drive up to be configurable.

Be sure you back up all data on the drive before doing this.

Question: Space being used up rapidly on a Mac's hard drive
MacFixIt reader Perry asks:

I have a MacBook Air mid 2011 version and my computer said I had no storage even though I cleared up 5GB the week before and didn't download anything this week but it dropped down to around 100MB I just got rid of a bunch of files to make it go to 2.5GB but then I went back to it a second later and it was down to 1.3 and then I went back again a few seconds later and it said 700MB. I have all of my big applications on my hard drive but it says I am using 23GB of "other." What is taking up all of my storage space?

Answer:
Hello, try downloading the program GrandPerspective and use it to scan your hard drive to display the files on it as squares of relative size. This will let you know if a specific file is growing massively, as it will appear as a single large square. You can then click this square and then click the Reveal button in the toolbar to show it in the Finder.

My guess is that an error in your system is creating a massive log file that is taking up space, and using GrandPerspective you can better determine this.

Question: Restoring a missing Safari browser in OS X
MacFixIt reader McCabe asks:

How do I go about getting my browser "Safari" back. I think it was deleted.

Answer:
You can reinstall OS X to restore Safari to it. This will reinstall included applications and the system software, but will not touch your user accounts and personal data organization and settings. Doing this depends on the version of OS X that you have installed on your system, but in OS X 10.7 and later you can reboot with Command-R held down to load the OS X Tools, which include an OS X installer.

Question: Tackling an iMac that continually shuts off
MacFixIt reader Fengtang asks:

I have got an early 2008 iMac, which has been working fine until last Friday when it restarted itself spontaneously while I was using Safari or other application. It became more frequently after each restart. I've heard of a couple of tricks before it reboot. I have Googled for possible fixes but have not been successful up to now. Changing to a new hard disk did not solve the problem either. I wonder if my logic board has gone as happened to many other iMacs. Any suggestion as to how to fix the problem is highly appreciated.

Answer:
Spontaneous reboots where the system seems to power off are either from a faulty logic board, a faulty power supply, or faulty wall power. If you know the circuit diagram of your home then you can try plugging your Mac into a different circuit (usually different floors have different circuits, and there are separate ones in kitchens and bathrooms than the rest of the house). Alternatively you can use an uninterruptible power supply (UPS) to smooth out any fluctuations in wall power that might be contributing to this issue. In addition you can try resetting the system's SMC and PRAM units, to hopefully clear any hardware parameters that might be the root of the problem. However, if this does not fix the problem, then you will have to take the system in for servicing to replace the logic board or power supply unit.

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