Just press and hold the power button on your Mac until it turns off. If you're selling, giving away, or trading-in your Mac and want to leave it in an out-of-box state, don't use the setup assistant or your previously connected Bluetooth devices, if any. After restart, a setup assistant guides you through the setup process, as if you're setting up your Mac for the first time.After joining a network, your Mac activates.Select all the files in the Caches folder. Click-hold Option and drag the Caches folder to your desktop as a backup in case something goes wrong. To select a Wi-Fi network, use the Wi-Fi menu in the upper-right corner of the screen. To manually clear cache files on Mac: Navigate to Go > Go To Folder. You might be asked to select a Wi-Fi network or attach a network cable.When reconnecting to a Bluetooth keyboard, you're asked to choose a language. If the accessory doesn't connect within 30 seconds, turn the accessory off and back on.

If it needs to reconnect to a Bluetooth accessory such as a keyboard or mouse, you might be asked to turn on the accessory. Your Mac restarts and shows a black screen or progress bar.Click Erase All Content & Settings to confirm that you want to proceed. Open it either by using Spotlight (Command-space) or by clicking the Apple logo in the upper left of the menu bar, choosing About This Mac, clicking the Storage tab, then Manage.If you're asked to sign out of Apple ID, enter your Apple ID password and click Continue.Click Continue to allow your settings, media, data, and the other listed items to be removed.Or click Continue to proceed without making a new backup. If you're asked to back up your Mac before resetting it, you can open Time Machine and back up to an external storage device.Enter the password that you use to log in to your Mac, then click OK. An erase assistant asks you to sign in with your administrator credentials.After choosing Erase All Content and Settings, follow these steps to continue:

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