Reinstalling/fixing corrupted OS

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So my macbook 2015, running 10.12.6, crashed after it got to 0% and couldn't boot, lesson learned.

However it couldn't repair, couldn't reinstall since I was stupid enough to buy a 250GB. So, I bought an external HDD with 1TB. Installed OS on that.

Now, everything is working fine, I still have all my files. But I'd like to get the OS on the machine again.

The external HDD doesn't come up as an option when trying to backup with time machine. In disk utility, I can see it has the same amount of space taken up as the machine, and if i try to boot without the external HDD it just shuts off.

So I'm assuming I'm booting from the external, and that has everything on it (please correct me if I'm wrong). When I try to recreate the machine from the external HDD it says "The source volume is readable and writable and cannot be removed from the desktop, so it cannot be copied block by block."

Should I change permissions? Or should I try to just press Delete on Macintosh HD? Just a bit worried since some of those 244GBs are very valuable to me.
Another thing is the Macintosh is included in the APPLE SSD SM0256G Media, which I can try to recreate from the external HDD aswell, but I'm worried that will mess something up.

Thanks for any replies!
 
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honestone33

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So my macbook 2015, running 10.12.6, crashed after it got to 0% and couldn't boot, lesson learned.

However it couldn't repair, couldn't reinstall since I was stupid enough to buy a 250GB. So, I bought an external HDD with 1TB. Installed OS on that.

Now, everything is working fine, I still have all my files. But I'd like to get the OS on the machine again.

The external HDD doesn't come up as an option when trying to backup with time machine. In disk utility, I can see it has the same amount of space taken up as the machine, and if i try to boot without the external HDD it just shuts off.

So I'm assuming I'm booting from the external, and that has everything on it (please correct me if I'm wrong). When I try to recreate the machine from the external HDD it says "The source volume is readable and writable and cannot be removed from the desktop, so it cannot be copied block by block."

Should I change permissions? Or should I try to just press Delete on Macintosh HD? Just a bit worried since some of those 244GBs are very valuable to me.
Another thing is the Macintosh is included in the APPLE SSD SM0256G Media, which I can try to recreate from the external HDD aswell, but I'm worried that will mess something up.

Thanks for any replies!

Welcome user121212. Hopefully we can help you with your issue.

So, taking this step by step:

1. You have a 2015 Macbook, with a 250 Gig internal SSD, and you run the last version of Sierra.

2. Unfortunately, you filled up that 250 Gig SSD, and your conjecture is that is what is preventing it from booting up.

If it is not booting up, how were you able to get all that information onto the 1 TB external drive?

As for "The external HDD doesn't come up as an option when trying to backup with time machine", where are you trying to backup that information to? (I don't use Time Machine, so maybe someone else who has more experience with TM can shed some light on that).

To confirm you are booting from the external drive, when the desktop appears, the main "boot" drive/partition on that external drive will appear first on the list that shows up on the desktop.

Do you have the original OS 10.12.6 Installation file? And are there any items you can remove from that 1 TB drive?

If you could provide answers to those questions, that would help immensely.
 
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Hey! So I could access the control menu at startup, the place where you can restore from time machine backup and whatnot. In that menu i tried to repair, but it didn't work.
Installing a new version of OS on the internal SSD didn't work because there wasn't enough space, so I installed it on an external HDD.

So when I boot up now, I log in like usual, the external HDD needs to be connected or else it won't start, the apple logo comes and the loading bar, then shuts off before completely loading. The external HDD does appear on the desktop, and I've gotten messages like "Please eject Macintosh HDD safely before you remove".

Accessing files are very slow as well, and it appears everything came with the installation of OS from the boot menu, as the external HDD has just as much space taken up as the internal SSD.

So, I need to get the external HDD copy onto the macintosh HDD, I think. But I'm a bit unsure if I'm completely off track in my thinking somehow as I don't know a lot about computers, and wanted to get some advice first. That's why I just tried making a backup first, or replacing the Macintosh HDD with the external one, where i get the "The source volume is readable and writable and cannot be removed from the desktop, so it cannot be copied block by block" error.

There is the delete Macintosh HDD option, but that's always a bit scary if you're not completely sure what's going on.
 
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honestone33

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Thanks for the additional information. Just to confirm, everything that was on your MacBook is now on the external HDD, correct? Also, did you partition that external HDD before "placing" everything from your MacBook onto it? If not (or if the partition on the external HDD is larger than 250 Gig), you will have issues in doing a restore.

And one more time: do you have a copy of the OS 10.12.6 Installation file? That will be a big help.
 
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@user121212
So I'm assuming I'm booting from the external, and that has everything on it


To confirm what volume you are booted from, just use About This Mac under the Apple icon, and it should show the name of the boot volume.

PS: I would strongly suggest you get another hard drives and store your valuable data on it using something like Carbon Copy Cloner immediately and before you try starting various repairs.


- Patrick
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Rod


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I'm puzzled, how did you manage to install an Operating System (OS) on the External Hard Drive (EHD)?

Currently I take it you are running off the EHD, that is, the OS in on the EHD and all your files are on the Internal Drive (SSD)?

My suggestion would be to copy all of your files and applications to the EHD. Most of these files will be in the Macintosh HD Folder which you should see in the side menu of any Finder window. If not check Finder Menu preferences and click Sidebar and tick everything, the "your name's" MacintoshHD is the one you want.
In that you will find Applications, Library, System and Users folders. You can just drag and drop these folders onto your EHD. Of course they will take a while to copy. Don't try to do more that one folder at a time.

The objective of that exercise is to have backups of all your personal data on the EHD so you can work on the internal SSD.

Once you have, say the contents of your Photos Folder, onto the EHD you can delete it from your SSD.

This will give you enough space to download the installer for macOS Sierra 10.12.6. Quit it once it loads (it will try to begin installation) just go to the Installer Menu on the menu bar and Quit it. Now you can copy it to the EHD. That way you will retain a copy in case the process goes sideways. The original on the SSD will be erased automatically when you use it.

I suggest then you run the installer on the internal SSD and select the erase and instal option.

Now you will have an empty SSD except for the macOS.

If all seems well you can reverse the process of transferring the data from the EHD to the internal SSD.

All of this probably sounds very complicated but step by step you will get there. There really is no simpler way. Most of the time will be waiting for data to transfer.

Make sure you have all of your passwords for everything.
 
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Yes, there's 253 GBs on the external HDD, and 245 on the macbook. Did not partition the external.. I'm not sure what/where the installation file is.
 
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Didn't know that! It says It's the external one. I'm thinking I might need to do that, I'll just buy another HDD today and do that, then return it or something.

But carbon copy cloner, does it show if the clone is bootable? Right now I can't boot from Macintosh HDD.
 
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@Rod

There's that menu you can still access if you can't boot properly, you can see time machine copies, access disk utility and reinstall OS and one more thing I can't remember. Even that was such a hassle, had to change the time cause it reset to 2016 and stuff.

I'm thinking about it, and I think I'll buy another HDD, do the carbon copy cloner on that, then go through your method. It'll be a bit time consuming but that's the safest way.
Then I'll just return one of the external HDDs, and keep one to start making real backups haha.
 
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But carbon copy cloner, does it show if the clone is bootable? Right now I can't boot from Macintosh HDD.

If the volume is not bootable, then I would expect any CCC clone of that volume would act the same.


Then I'll just return one of the external HDDs, and keep one to start making real backups haha.
I would strongly suggest that you do not return any Hard Drive and keep both. Only having one backup Drive is absolutely minimal insurance against any loss, and you seem to have some rather critical data that you do not want to lose.


- Patrick
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honestone33

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If the volume is not bootable, then I would expect any CCC clone of that volume would act the same.



I would strongly suggest that you do not return any Hard Drive and keep both. Only having one backup Drive is absolutely minimal insurance against any loss, and you seem to have some rather critical data that you do not want to lose.


- Patrick
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@user121212

That's excellent advice from Patrick. I have 2 external Samsung SSDs that I use for SuperDuper! backups for each of my Macs.

Also, he is absolutely correct about CCC (or SuperDuper!) not being able to make a bootable clone of your non-bootable system on your internal SSD.
 
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@honestone33
Yes, there's 253 GBs on the external HDD, and 245 on the macbook. Did not partition the external.. I'm not sure what/where the installation file is.

So, I suspect you are using 253 Gig of space on that 1 TB external drive, with only 1 partition. Thus, you will have difficulty in terms of trying to do a complete of restore from that backup. That's because while the amount of space used is about the same, the normal Restore process sees the entire 1 TB amount.

And the post by Rod above is excellent, as it is the way to go. The only step I would suggest be added is that after copying the OS 10.12.6 Installer file onto the external HDD, and after booting your machine from that external HDD, you then first run Disk Utility from there to analyze the internal SSD inside your MacBook. You can then Erase and Format it (assuming there is nothing seriously with it). Then, launch the OS 10.12.6 Installer file and do a clean installation of OS 10.12.6 onto that internal SSD. When that installation is complete, you'll be offered the opportunity to migrate/copy needed information from your backup. However, since you earlier indicated that the cause of the original issue was that you filled up that internal SSD, migrating everything could be an issue. Yet, you now have a backup of that original "stuffed" system, so maybe after doing the migration, you can delete some large files from the internal SSD. And when you get the additional HDD, it would be best to partition it first, with one of the partitions being 300 Gig, and then use CCC to clone the information from your current 1 TB drive onto that partition. You would then two backups of your original system.
 
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Thus, you will have difficulty in terms of trying to do any kind of restore from that backup. That's because while the amount of space used is about the same, the normal Restore process sees the entire 1 TB amount.



WHAT...??? That is completely nonsensical.


- Patrick
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It's not nonsensical. I was talking about trying to do a COMPLETE restore.


Then maybe you might care to explain your original paragraph and reasoning a bit better and your logic for your statement, and do so before doing any further later post-editing.

Your statement doesn't make sense to me and not quite logical, but then again, maybe I just misunderstood something and user121212 the OP understands completely.



- Patrick
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honestone33

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Then maybe you might care to explain your original paragraph and reasoning a bit better and your logic for your statement, and do so before doing any further later post-editing.

Your statement doesn't make sense to me and not quite logical, but then again, maybe I just misunderstood something and user121212 the OP understands completely.



- Patrick
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You first need to point out which original paragraph you are talking about. The post I made just prior to your nonsensical-stated one is clear enough.

If one tries to do a COMPLETE RESTORE of a drive/partition that is taking the same or less amount of space than the destination drive/partition, but the overall size of that drive/partition is larger then the size of the destination drive/partition, one will get an error. On the other hand, when doing a migration of data from such a larger overall sized drive/partition will work fine.

Maybe (and hopefully) this is clear enough for you:

macos - OSX: How can I clone a larger hard drive to a smaller one? - Super User
 
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Maybe (and hopefully) this is clear enough for you:
macos - OSX: How can I clone a larger hard drive to a smaller one? - Super User

That article is dealing with two completely separate issues:
• I want is an exact clone, byte-for-byte.
• I'm using FileVault on the old drive.


BTW: One could always just use the Finder to select all the needed existing files and folders and then move from the larger to the smaller Drive as long as that drive has enough spare room to hold them all.



- Patrick
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To try to calm things down a bit, there are at least two types of "clone" processes. One is a block-for-block or byte-for-byte clone and the other is a file by file clone. You can definitely clone a bigger drive to a smaller drive as long as the data on the larger drive is smaller than the smaller drive in a file by file clone. That's not a byte-for-byte clone, which goes even further and requires that the two drives absolutely match in geometry (platters, heads, sectors, etc). But for a file-by-file clone, as long as it fits on the smaller drive, it works perfectly. I've done it many times before.

As for the unbootability of the internal drive, could it be that because the drive is so full that the OS is unable to establish scratch and cache space on it, hence it won't boot. If that is the case and if you get a new drive and CCC, do a full clone to a larger drive, including the system files following the directions at the CCC website, it may well boot from the external because it has the room. Then you can boot from it, then go back to the internal to look to clean up some space on the internal to make enough space for it to boot. If it fails to boot from the CCC Clone, then you will know that the internal drive has system problems that got cloned over and so will need to have a full reinstall done.
 
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there are at least two types of "clone" processes. One is a block-for-block or byte-for-byte clone and the other is a file by file clone.


Thanks for providing the extra additional information Jake, especially for the benefit for those who didn't know or realize how such stuff can work.

I could never understand why a user would want or insist on a block by block backup or clone.

But I believe CCC and some other software could do so as an option many versions ago. or maybe still can.

EDIT:
CCC and The Block-Level Copy
If enabled in CCC's preferences, CCC will indicate if the source and destination volume selections qualify for a block-level copy.
The Block-Level Copy | Carbon Copy Cloner | Bombich Software



- Patrick
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