Be prepared for this to take anywhere from 20 minutes to several hours, depending on your connection. OS X downloads over the Internet from Apple’s servers, and is installed. Enter the network’s password, if necessary.Ĭhoose Reinstall OS X and click Continue. Click the Wi-Fi icon at the top right of the screen and choose a network. You can do this, in theory, without harming your files and settings.įor this option to work in OS X Recovery, you must be connected to the Internet. Sometimes your copy of OS X is the problem and you’ll need to install it anew. You might need to reformat the drive and reinstall OS X.You might need a better repair utility (see Macworld’s Do you need a third-party disk utility?).If Disk Utility repairs your drive-or can’t find problems to repair-but the problem still occurs, try reinstalling OS X. ⑤ Once in Recovery mode, you can select your startup drive and click Repair Drive (circled). If it’s possible to add more RAM, click the Memory Upgrade Instructions link. To see how much you have, choose Apple  > About This Mac and click Memory ③. Add RAM: Yosemite demands a lot of RAM if everything is running slowly, and it’s not due to a full drive, you might need more.To see what files are hogging your megabytes, try an app like Id-design’s WhatSize. Free up disk space: If your disk is nearly full, your Mac may run slowly.Check vendor Web sites for apps you got elsewhere. Go to Apple  > App Store and click Updates to check for, and then download, new versions of software from the App store (including OS X itself).

Update your software: If your problem is a bug, a software update may help.If force-quitting and restarting doesn’t stop your slowdown problems, you might need to do more: If your Mac still won’t start, take it to the Genius Bar.Trying resetting your Mac’s SMC (System Management Controller).Did you recently install new RAM? Take it out.Do you have another power cable (or, for laptops, another power adapter)? Try that.Is your power cord damaged? Check for chew marks if you have a kitten, puppy, or other teething beast.Does the electrical outlet work? Plug in a lamp to test it.Are you staring blankly at this chapter because you can’t even get your Mac to turn on? Try this:

How to open mac os x utilities