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Do I need to format a disk drive before reinstalling my OS?

I've ran into a problem with XCode where it keeps crashing on startup, and I thought of reinstalling macOS Sierra but I'm actually nervous that it might screw things up. I've seen videos on Youtube but they format the drive then reinstall. Should I reinstall macOS Sierra only without formatting my drive?

MacBook Pro Retina

Posted on Sep 16, 2019 9:54 PM

Question marked as Top-ranking reply

Posted on Sep 16, 2019 10:15 PM

It is a bit extreme to delete your OS and reinstall just because Xcode isn't starting up. Have you booted to your Recovery HD

and run Disk Utility> First Aid. Or you could install the Combo update, https://support.apple.com/kb/DL1931?viewlocale=en_US&locale=en_US install it over what you have got it'll reset some system files and caches.

Or you could delete Xcode and then re-download and install it.

Reinstalling an OS should be a last resort.

22 replies
Question marked as Top-ranking reply

Sep 16, 2019 10:15 PM in response to Community User

It is a bit extreme to delete your OS and reinstall just because Xcode isn't starting up. Have you booted to your Recovery HD

and run Disk Utility> First Aid. Or you could install the Combo update, https://support.apple.com/kb/DL1931?viewlocale=en_US&locale=en_US install it over what you have got it'll reset some system files and caches.

Or you could delete Xcode and then re-download and install it.

Reinstalling an OS should be a last resort.

Sep 26, 2019 12:45 AM in response to Community User

Just gonna plop this right here.


" Do I need to format a disk drive before reinstalling my OS?"


Without description context, by all means, yes. Reinstalling your OS doesn't require you to format your disk drive.


But with the description context, upgrading to High Sierra and using Xcode 10 fixed my issue.

Sep 18, 2019 9:11 AM in response to Community User

xteal Said:

I restarted into recovery mode and was only able to first aid the APPLE SSD SM0256G Media HD (macintosh HD didn't let me first aid), do I also first aid the OSX Drive as well that also appears?

———


If you cannot perform this reinstallation nor run First Aid from Recovery Mode, then I think this has just what you need:

How to Create and Use a Bootable Installer for macOS - Apple Support

Sep 23, 2019 8:01 PM in response to Community User

Rather than reinstall High Sierra through a remote connection, then using another Mac Create and Use a Bootable Installer for macOS.


Will this work? I think it may.


If not, then reserve a Genius Bar Appointment at your Local Apple Store. There all will be looked into.


Or, maybe it’s time for a new hard drive. With a non-optimized Hard Drive and a Lined-Scrren, have this looked at. See what can be done.

Sep 21, 2019 11:16 AM in response to Eau Rouge

Ok, I was getting a little bit hopeless... So I reinstalled macOS Sierra.


After that, I went to go open XCode and it asked to install required tools, and it did install it. After opening it again, instant crash.


So I went to go install the macOS Combo Update, FYI I was on 10.12.6 (16G29) during the time


The combo update acted weird, it didn't show my drive but it did allow me to install, which I did.


After installing I then had version... 10.12.6 (16G29) The same version.


Opening XCode resulted in the same thing, but going back to the combo update, it actually showed my drive & allowed me to install the combo update again.


Should I install the combo update again? Or just upgrade to macOS High Sierra?

(Also, a couple questions about moving from Sierra to High Sierra)

  • Should I be concerned about High Sierra erasing all my files?
  • What will Sierra do?
  • Why is the installer 22mb?
  • Making a backup is optional.. right?

Sep 16, 2019 11:20 PM in response to Eau Rouge

how much exactly does the combo update take up? I have 116GB free and it says I'm not able to install due to "volume issues" . Disk Utility on a user account didn't work, haven't tried recovery mode disk utility yet. Plus I've heard a couple of things about macOS Recovery tools. Cmd+Q does something? Do I have to X out the utilities window?


Image:

Sep 17, 2019 9:41 AM in response to Community User

To answer your question, you can reinstall Sierra without reformatting the hard drive. As VikingOSX suggested, you might consider upgrading to High Sierra.


Check to make sure your applications are compatible.        


Application Compatibility


Also check to make sure there is a compatible driver for your printer.


Do a backup before installing, preferable 2 backups on 2 different drives.

Sep 19, 2019 12:05 AM in response to Eau Rouge

I mounted my macintosh hd, and first aid'd it. I exited disk utility and exited macOS Utilities. I clicked on startup disk instead of restart and xcode crash & the volume issue thing on the updatescombo.pkg still persists. I just keep repeating this task?

Sep 20, 2019 12:48 AM in response to Community User

What I've tried so far should be crossed off the list.


Safe Mode - I shut down, waited about 30 seconds, turned on in safe mode (hold shift) then logged in twice, what I noticed was how there were a lot of lines on the screen, I don't know how to describe it but it just was like that. Then I shut down, waited 30 seconds, went into recovery mode, first aid'd macintosh HD, shut down, went back in normal mode.


Recovery Mode Disk Utility - Restarted, went in recovery mode, disk utility, first aid'd macintosh HD.


Combo Update - Can't even do the combo update since the "volume does not meet the following requirements"

Sep 23, 2019 6:58 PM in response to Eau Rouge

I am now on macOS High Sierra, (10.13.6 (17G65)) and XCode 9.2 prompted me to install, and still crashes. I am now installing Xcode 10 (I believe it should work since the downloads say that XCode 10 has command line tools for macOS 10.13)

Do I need to format a disk drive before reinstalling my OS?

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