You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

macOS Big Sur won't finish installing

Hi Im not very good with IT so sorry if my questions sound stupid. Im trying to install BigSur (have Catalina atm) but it won't finish installing. I get a message saying unable to install on Mac HD - but no option to put it elsewhere either (not sure whether I should be able to). My Mac is a bit dated but says I had 12.+ GB left out of 121+ storage. Surely this is sufficient ?


[Re-Titled by Moderator]

MacBook Air 13″, macOS 10.15

Posted on Jan 15, 2022 2:23 AM

Reply

Similar questions

12 replies

Jan 15, 2022 3:14 AM in response to MattsMom22

Tips How to Upgrade to Big Sur 


There are several points to consider before attempting the upgrade to Big Sur. The most important is Due Diligence on the part of the User and is a Prerequisite for a smooth upgrade.  


The below points should all be consider Before attempting the upgrade.


Point # 1 - Are there pre-existing Unresolved Software Issues. They should be resolved prior to upgrading - they may carryover to Big Sur making the system unstable / unusable.


Point # 2 - Are there any AntiVirus, Disk Cleaner, Optimizers, Un-installers, etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS and may even Corrupt the OS requiring a Reinstallation. The The Built in Security  is all that is required.


Point # 2 A - Commercial VPNs should only be used if Mandated by Corporate Head Office for working remotely. Otherwise - ones Privacy and Security touted by the VPN is suspect.


Point # 3How to get old versions of macOS  ie: Empty Space Requirements specific to the Big Sur. Apple states 35.6 GB Empty Space but suggest 50 GB


Point # 4 - Does the intended computer qualify for the upgrade.


Point # 5 - Are the installed Applications / Extensions compatible with Big Sur. Check with the Developer for compatible Apps / extension or do they offer updates. Same goes for Third Party Drivers for Printer, Scanners etc.


Point # 6 - If upgrading from Mojave and earlier versions of macOS - Remember that Big Sur does not support anything 32 bit. These include Applications, Extensions and Drivers for any devices. There is no workaround.


Point # 6A - To check for 32 bit Applications - a good application to use is Go64 - safe to use.


Point # 7 - Do I have a Rescue Plan In-Place. This comprises having 3 Backups using 2 methods and 1 Off Site incase of Theft, Loss or Natural Disasters. A Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS. For addition purposes - two Tested Bootable Clones each to separate external drives. This is insurance incase the upgrades goes sideways. At least one Tested Clone and / or Time Machine Backup should be Off - Site


Point # 8  - To upgrade to Big Sur will requires a quick, stable and reliable Internet Connection - preferred method is via Ethernet Connection. 


If not available and using Wifi - move computer as close to the Access Point / Router and disconnect all other devices connected to Wifi. Want the maximum bandwidth for the computer being upgraded to Big Sur.

Jan 15, 2022 3:14 AM in response to MattsMom22

What is “Other” storage on a Mac, and how can I clean it out?


Free up storage space on your Mac


OmniDiskSweeper Safe to use


GrandPerspective 


How to delete Time Machine snapshots on your Mac


See used and available storage space on your Mac


The final word from Apple on Managing the " Other " Category


Other: Contains files that don’t fall into the categories listed here. This category primarily includes files and data used by the system, such as log files, caches, VM files, and other runtime system resources. Also included are temporary files, fonts, app support files, and plug-ins. You can't manage the contents of this category. The contents are managed by macOS, and the category varies in size depending on the current state of your Mac.

Jan 15, 2022 8:15 AM in response to MattsMom22

Thanks for this very detailed reply but most of it doesn't mean anything to me as Im not sufficiently IT literate and therefore dont know the answer to most of the questions you pose in most of your points.


From what I can understand it seems that I need 30GB of storage in order to install this. I know I had about 20GB before starting to install this so does that mean that I can't install BigSur, in which case should I try and uninstall/delate it ?



Jan 15, 2022 12:28 PM in response to PRP_53

Thank you - I appreciate your reply but Im so inexperienced using the Mac &IT generally, Im not sure. There were no unresolved issues and I dont think I have a VPN and i assume my computer qualifies. I dont know if I have another old version as I thought previous ones were automatically deleted on new upgrades.


As you say at least 30 G is needed for the update - I know I only had about 20 G available so that will mean I can't install it anyway.



Jan 16, 2022 3:46 AM in response to MattsMom22

MattsMom22 wrote:

So if I see in Finder - Apps “install BigSur” am I correct in thinking it’s not really there and I can safely delete it


That will depend.


If this computer is running Catalina macOS 10.15 - yes.


If thus computer is already running Big Sur macOS 11 - no


Use About this Mac from the Apple Icon on Desktop - the required Information will be there.




Jan 16, 2022 4:45 AM in response to PRP_53

Thank you for your help. It does say Catalina on the About my Mac so I will try to uninstall Big Sur as I obviously don’t have enough space. I only have 19+GB left out of 121+GB so if I need 30 (or preferably 50) that’s a massive amounts out of that. Sounds like a new machine is needed 🥴☹️

it also says Install High Sierra- so presumably I can get rid if that too?

Jan 16, 2022 4:52 AM in response to MattsMom22

Yes High Sierra a too can be removed.


Suggestion - Remove both Big Sur and High Sierra and then empty the Trash Bin


Restart the computer normally and check how much Empty Space the computer is showing.


One might be pleasantly surprised ( hopefully ) the Empty Space being reported will have increased to the need 30 GB or more.


If that does occur - one may decide if upgrading to Big Sur is viable.


macOS Big Sur won't finish installing

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.