MacFixIt Answers is a feature in which I answer Mac-related questions e-mailed in by our readers.
This week, readers wrote in with questions about completely wiping a Mac back to factory settings similar to what can be done with an iPod or iPhone, restoring a lost administrative account, removing the account of someone who no longer uses the system, and restoring lost programs that were included with OS X. I welcome views from readers, so if you have any suggestions or alternative approaches to these problems, please post them in the comments!
Question: Completely wiping a Mac back to factory settings
MacFixIt reader Sheikh asks:
I'm trying to restore my 2009 MacBook Pro. I'm running Mountain Lion, but I'd like restore it like you would restore an iPhone. In other words I want to wipe it completely and just reinstall Mountain Lion so that it would also wipe out whatever I currently have.
Do you have a backup of your system? If not then that would be the first thing to do. Create a Time Machine backup just in case you want to save anything.
Make sure you have access to the Internet. Reboot the system with the Command-R keys held down, then choose Disk Utility from the OS X Tools window and use this to select your hard drive and erase it (use the Erase tab). Then quit Disk Utility and use the Install OS X option from the Tools window to reinstall OS X on this drive. You will need an Internet connection to download the approximately 4GB of installation files so this may take a while, but once it's done you'll have a fully formatted and fresh system to work with as if you just bought it from Apple.
Question: Restoring a lost administrative account
MacFixIt reader Morten Bo asks:
I deleted the Admin user on my account. From the beginning I have created 2 user accounts on my Mac (One of them the Admin account). I can still sign in through account No. 2, but trying to recreate the user Admin account I deleted doesn't work. I remember the Admin settings, but because my Mac will not approve username and password I'm now trying to log in and change in User and groups.
Can you by any chance help me to recreate the Admin User? All the Admin user files and libraries are still available in/on the Macintosh HD/User library.
This can be easily done several different ways, but the quickest is to remove a small hidden file from the system and thereby force it to use the setup assistant again. In here you can create a new admin user account, which you can then use to recreate any old lost accounts. You can follow the .
Question: Removing an unused account
MacFixIt reader BP asks:
I bought my daughter a MacBook Pro, so no longer need her account on our Mac. How can I delete her account and recover the space?
To delete a user account go to the Users & Groups system preferences and then authenticate as an administrator by clicking the lock. Then select the desired account in the Accounts list and click the minus sign to remove it. Following this you will have the option to entirely delete the account, archive its documents and settings, or leave the documents and settings as is. If you choose not to delete the account, you can go to the system's Users directory later and manually remove the account's home folder to reclaim any space that it uses.
Question: Restoring lost programs that came with OS X
MacFixIt reader Richard asks:
I have a problem with both Preview and Photo Booth on my iMac, which are both missing from my Mac. They are in my Dock but like an empty page with a pencil, rule, and brush through that page. What is the best way to put them back in the Dock and use them? I am on Snow Leopard 10.6.8 and I want to switch to Mountain Lion, if I switch without repairing those two applications, will Mountain Lion repair them automatically?
Reinstalling OS X should restore these programs. Additionally, upgrading to Mountain Lion should install new versions of them for you. I would recommend the latter since you are already planning on doing it. This will also give you a more convenient way to recover from such errors in the future, by installing the Recovery HD partition on your system, which you can boot to and reinstall OS X or restore from backups.