I'm currently running MacOS Big Sur and every time I try to install Windows 10 I get the same "disk could not be partitioned error message". I don't use time machine of filevault I've tried running first aid. I also attempted to run /sbin/fsck -fy from single user mode but it told me that repairs aren't available on mounted disks yet. I also tried to format the disk to HFS+ but when I went to erase my disk from recovery mode that wasn't an option.
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Bootcamp cannot partition disk
- Thread starter JolyGolf_
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You will find that is common going back even to 2007. You need contiguous free space and can't have files locked that can't be moved.
Search of Google Apple BC Assistant you see
support.apple.com
Search of Google Apple BC Assistant you see
If Boot Camp Assistant says that your disk could not be partitioned - Apple Support
Boot Camp Assistant might say that an error occurred while partitioning the disk for Windows.
Yes I did everything in that guide and more (including single user mode manipulations) and nothing changedYou will find that is common going back even to 2007. You need contiguous free space and can't have files locked that can't be moved.
Search of Google Apple BC Assistant you see
If Boot Camp Assistant says that your disk could not be partitioned - Apple Support
Boot Camp Assistant might say that an error occurred while partitioning the disk for Windows.
Either what IowaLynn said above -- repartition your drive, install clean MacOS, run Bootcamp
I have had to do this several times.
or
Use Hasleo's WinToUSB to install Windows 10 to an external USB Drive. You will need to run it on a Windows device.
I have had to do this several times.
or
Use Hasleo's WinToUSB to install Windows 10 to an external USB Drive. You will need to run it on a Windows device.
Hey, I have the same issue after updating to Big Sur (2017 15" MBP). Did you manage to solve it?
I have the same issue as both of you, and also have exhausted all of the troubleshooting steps I could find online. Which macs do you have? Mine has the Fusion Drive, which I think is causing my problems
I have the same Issue too mine being a (15-inch, Mid 2015) tell me if any of you find a fix
Real misery loves company hours here. Have any of you tried reformatting and reinstalling MacOS? I've seen folks have success going that route, but it's my wife's primary machine and she hates when I do this stuff. I'm worried if I go that route and still can't run Bootcamp she may actually kill me.
Same issue here with Mac Mini 2018. I tried every official and unoffical path. Only thing that worked for me was the last resort, which was to create Time Machine backup, wipe entire disk and recreate Mac partition and reinstall OS cleanly in Recovery Mode. Then I applied the backup on initial setup. And now it works on first try.
I’m glad to hear the nuclear option worked. Did you wipe the disk like you would when selling it? I’ve only done so once or twice before and it’s been a while.
Yes. Normally. Booted into Recovery OS via (Command + R). Then I accessed Disk Utility selected whole root Apple SSD Drive, clicked Erase option, choose "Macintosh HD" as partition name, APFS as format, GUID as scheme and then clicked Erase. After the partition was created, I quit Disk Utility. Then in the main menu again I choose Reinstall macOS Big Sur, choose Macintosh HD and after reinstall was complete I applied Time Machine backup as I would do on a brand new Mac.
I have done the same a couple of times with my 2015 27" iMac.
- Backed up (thrice, once with Time Machine, once with Carbon Copy Cloner and a third copy just of the Users folder (Paranoid, I am))
- Gone into Recovery Mode, rebuilt Fusion Drive with 'diskutil resetFusion'. This splits the drive, rebuilds it, reformats it. Absolutely clean.
- Used "Reinstall macOS" command to install a fresh new system directly from the Apple servers. (This takes some time, so you can go away, harvest some coffee beans from the tree, dry them, roast them, grind them, make coffee.)
- Reboot, set up users (I have three), restore their files, re-install essential apps.
I did this but it wouldn't work, I restored my files using Time Machine though after reinstalling the OS, do you think this re-introduced the bug? If so is there any way I can restore my files differently (wife will kill me if I lose her data!)?
You want to do the bootcamp first before using migration assistant to restore.
That gives bootcamp the best chance of getting a partition created.
I'm on a mac mini 2012 with catalina and i got past the partition error. Not 100% sure what i did but i think it was this. Because i read that OSX locks files on a position on the disk, it wouldn't partition in bootcamp because it can't move these files.
I erased the disk and made 2 partitions with disk utility and installed catalina on the first (locking files in the first part of the disk) Ran the bootcamp assistant again and it made it back into 1 partition. Then i started bootcamp manager again and no more partition error.
Also i did not update catalina after the install. I guessed this is oldschool hardware that makes newer software buggy. Not sure if it helped.
Now i'm stuck at the windows install at the disks where it won't go next when it's selects the BOOTCAMP partition.
Edit: PRAM reset before making 2 partitions through bootcamp assistant fix it. No format as i've seen others do of BOOTCAMP partition in windows setup. Just press next started the installation.
Edit 2: I should have downloaded the iso straight from microsoft. Didn't get past the big 2017 install which i had to download from the web. Also mac partition was not visible for a long time. Just the op restart in OSX didn't work but the mac disk showed up in the select startup disk later in the windows updates. Had snow tv screen flicker to black and back first time in windows during bootcamp driver install and more hangs in mac later during updates. Pram reset did the trick. Thought i broke my catalina install.
Edit3: doing a web update assistant install of h2h 2022 now. Startech displayport splitter small to big works on 1 monitor. Need to get another DP capable display.
I erased the disk and made 2 partitions with disk utility and installed catalina on the first (locking files in the first part of the disk) Ran the bootcamp assistant again and it made it back into 1 partition. Then i started bootcamp manager again and no more partition error.
Also i did not update catalina after the install. I guessed this is oldschool hardware that makes newer software buggy. Not sure if it helped.
Now i'm stuck at the windows install at the disks where it won't go next when it's selects the BOOTCAMP partition.
Edit: PRAM reset before making 2 partitions through bootcamp assistant fix it. No format as i've seen others do of BOOTCAMP partition in windows setup. Just press next started the installation.
Edit 2: I should have downloaded the iso straight from microsoft. Didn't get past the big 2017 install which i had to download from the web. Also mac partition was not visible for a long time. Just the op restart in OSX didn't work but the mac disk showed up in the select startup disk later in the windows updates. Had snow tv screen flicker to black and back first time in windows during bootcamp driver install and more hangs in mac later during updates. Pram reset did the trick. Thought i broke my catalina install.
Edit3: doing a web update assistant install of h2h 2022 now. Startech displayport splitter small to big works on 1 monitor. Need to get another DP capable display.
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For a drive without any content, this is what I do:
1. Boot using macOS bootable installer then run Disk Utility.
2. On Yosemite or El Capitan and older, a bit unsure about the macOS version, you can partition the disk without erasing it first.
3. I'm using Catalina so I have to erase the disk first then partition it into two.
4. I erase it as HFS+ (macOS extended, journaled) then partition it into two.
5. The other half, I set it to MS-DOS/FAT (which is actually FAT32).
6. I close Disk Utility and proceed with macOS installation.
7. I have downloaded the Boot Camp Windows drivers using brigadier from github so I do not run Boot Camp from within macOS.
8. I boot the Mac using the bootable Windows installer and format the FAT32 partition as NTFS then proceed with Windows installation.
9. Once Windows is installed, I run the setup for the downloaded Boot Camp drivers.
1. Boot using macOS bootable installer then run Disk Utility.
2. On Yosemite or El Capitan and older, a bit unsure about the macOS version, you can partition the disk without erasing it first.
3. I'm using Catalina so I have to erase the disk first then partition it into two.
4. I erase it as HFS+ (macOS extended, journaled) then partition it into two.
5. The other half, I set it to MS-DOS/FAT (which is actually FAT32).
6. I close Disk Utility and proceed with macOS installation.
7. I have downloaded the Boot Camp Windows drivers using brigadier from github so I do not run Boot Camp from within macOS.
8. I boot the Mac using the bootable Windows installer and format the FAT32 partition as NTFS then proceed with Windows installation.
9. Once Windows is installed, I run the setup for the downloaded Boot Camp drivers.
Yep that pre partition is the way to go. I even have my Thunderbolt Magma 3T with AMD HD 7950 rack working on catalina with Kryptonite. But i need to find an older Windows version 1803 or something to get it working on Windows 10. And an UEFI partition instead of a Legacy bios for Kryptonite so I see the windows disk on startup and can select it.