• Reset//rest Mac Os Catalina
• Mac Os Versions

Start up from macOS Recovery

This is always the first step before reinstalling an operating system. So delete all unneeded files then backup the rest either on cloud storage, a USB stick, or a removable hard-drive. Remember to also backup your iTunes library, your iMovie database, and your Photos database.

Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:

Apple silicon

• Let go of the keys and let your Mac reboot normally. When you log back in, you’ll probably will have to adjust your mouse speed, time and date/timezone, and a few other things, but otherwise you.
• Step 8: Reinstall your operating system. Congratulations, you’ve reformatted your hard drive and reset your Mac to factory settings. Now you can reinstall your operating system. Simply click Reinstall macOS from the utilities menu. Confirm that you really want to do it and follow the instructions you’ll see on the screen.
• Jan 13, 2021 8 Reinstall your operating system. Once you have disabled all the licensed applications and erased all the data from your device and hard drive, now it’s time to reinstall the operating system. Simply in the macOS utility menu, select the option of reinstall macOS. Follow the instructions in the wizard to complete the reinstallation.

Turn on your Mac and continue to press and hold the power button until you see the startup options window. Click the gear icon labeled Options, then click Continue.

Intel processor

Make sure that your Mac has a connection to the internet. Then turn on your Mac and immediately press and hold Command (⌘)-R until you see an Apple logo or other image.

If you're asked to select a user you know the password for, select the user, click Next, then enter their administrator password.

Reset//rest Mac Os Catalina

Reinstall macOS

Select Reinstall macOS from the utilities window in macOS Recovery, then click Continue and follow the onscreen instructions.

Follow these guidelines during installation:

• If the installer asks to unlock your disk, enter the password you use to log in to your Mac.
• If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.
• If the installer offers you the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.
• Allow installation to complete without putting your Mac to sleep or closing its lid. Your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time.

After installation is complete, your Mac might restart to a setup assistant. If you're selling, trading in, or giving away your Mac, press Command-Q to quit the assistant without completing setup. Then click Shut Down. When the new owner starts up the Mac, they can use their own information to complete setup.

Other macOS installation options

Mac Os Versions

When you install macOS from Recovery, you get the current version of the most recently installed macOS, with some exceptions:

• On an Intel-based Mac: If you use Shift-Option-Command-R during startup, you're offered the macOS that came with your Mac, or the closest version still available. If you use Option-Command-R during startup, in most cases you're offered the latest macOS that is compatible with your Mac. Otherwise you're offered the macOS that came with your Mac, or the closest version still available.
• If the Mac logic board was just replaced, you may be offered only the latest macOS that is compatible with your Mac. If you just erased your entire startup disk, you may be offered only the macOS that came with your Mac, or the closest version still available.

You can also use these methods to install macOS, if the macOS is compatible with your Mac:

• Use the App Store to download and install the latest macOS.
• Use the App Store or a web browser to download and install an earlier macOS.
• Use a USB flash drive or other secondary volume to create a bootable installer.

Q: iOS prompted me for access to Contacts when I first launched my app, which uses the NSContactsUsageDescription key.I was not prompted in the subsequent runs of my app. How do I get prompted again?

A: When your app, which uses a purpose string (also called usage description), attempts to access user's data, the system displays a consent alert that allows the user to grant or deny access to them such as the ones shown in Figure 1 and Figure 2.

The consent alert only appears the first time your app asks for permission. To display it again, you must reset privacy settings on your device or system.

• For iOS apps, tap Settings > General > Reset > Reset Location & Privacy on your device to reset all location and privacy settings for your app as shown in Figure 3.

  Important: Using Reset Location & Privacy will reset location and privacy settings for all services on your device.

• For iOS Simulator apps, delete the app from the Simulator or tap Settings > General > Reset > Reset Location & Privacy in the Simulator to reset all location and privacy settings for your app.

  Important: Using Reset Location & Privacy will reset location and privacy settings for all services in the Simulator.

• For macOS apps, use the tccutil command line tool, which allows you to reset access for all applications to a specific service in Terminal as follows:

  where service is the name of the service for which privacy settings will be reset. See Listing 1, Listing 2, and Listing 3 for examples on how to reset permissions for Contacts, Calendar, and Reminders, respectively.

  
  

  Listing 1 Reset all permissions for Contacts.

  
  

  Listing 2 Reset all permissions for Calendar.

  
  

  Listing 3 Reset all permissions for Reminders.

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