Reset a second-hand Mac
I’ve bought an iMac that’s a few months old. How can I reset it to its original state (deleting basic data including photos and music, emails and so on)? Stan Shilton You can’t just delete the previous user’s data and settings. This copy of OS X is tied to their Apple ID and you won’t be able to install updates without their password. Instead, you need to erase the disk and start again. Restart the iMac with å+ç+R held down to launch Internet Recovery. From the menu, open Disk Utility and select the icon for your hard disk (not the volume icon underneath it). Click the Partition tab and reformat the disk with default options – the Partition Map Scheme should be ‘GUID Partition table’, the Partition Layout ‘1 Partition’ and the Format ‘Mac OS Extended (Journaled)’. Click Apply; all the data on that disk are permanently erased. After that, run the OS X Installer from Internet Recovery menu. This needs an internet connection because it downloads OS X from the App Store. When done, the iMac will restart and run the Setup Assistant. This will help you set up your email account and copy settings and documents across from another Mac or Windows PC if you have one.