Have the same problem like here https://discussions.apple.com/thread/250633590
iMac (Retina 5K, 27-inch, Late 2015)
macOS Catalina 10.15.1 (19B88)
When external hdd connected i see this one:
after remove at all times get this. restart not helps...
iMac 27", macOS 10.15
Tumbles1982 wrote:
Is there a work around for this? a config file that can be edited to make bootcamp assistant disregard checking if there's a second drive in the system?
Yes, by using a standard partitioning scheme that BC Assistant supports.
How could a totally unrelated second internal drive somehow make running bootcamp assistant not possible?
The 'second' (or nth) disk is on the same connection, and is visible to the installer, firmware, applications, etc.,.
The only Mac on which multiple independent internal drives are supported by BC Assistant is the legacy Tower MacPro. On such towers, the only supported configurations are
BCA uses the Mac Model Identifier and supported disk layouts to allow partitioning.
** Checking the container superblock.
** Checking the EFI jumpstart record.
** Checking the space manager.
** Checking the space manager free queue trees.
** Checking the object map.
** Checking volume.
** Checking the APFS volume superblock.
** The volume Macintosh HD - Data was formatted by diskmanagementd (945.241.4) and last modified by apfs_kext (1412.41.1).
** Checking the object map.
** Checking the snapshot metadata tree.
** Checking the snapshot metadata.
** Checking the extent ref tree.
** Checking the fsroot tree.
** Checking volume.
** Checking the APFS volume superblock.
** The volume Preboot was formatted by newfs_apfs (748.21.6) and last modified by apfs_kext (1412.41.1).
** Checking the object map.
** Checking the snapshot metadata tree.
** Checking the snapshot metadata.
** Checking the extent ref tree.
** Checking the fsroot tree.
** Checking volume.
** Checking the APFS volume superblock.
** The volume Recovery was formatted by newfs_apfs (748.21.6) and last modified by apfs_kext (1412.41.1).
** Checking the object map.
** Checking the snapshot metadata tree.
** Checking the snapshot metadata.
** Checking the extent ref tree.
** Checking the fsroot tree.
** Checking volume.
** Checking the APFS volume superblock.
** The volume VM was formatted by newfs_apfs (748.21.6) and last modified by apfs_kext (1412.41.1).
** Checking the object map.
** Checking the snapshot metadata tree.
** Checking the snapshot metadata.
** Checking the extent ref tree.
** Checking the fsroot tree.
** Checking volume.
** Checking the APFS volume superblock.
** The volume Macintosh HD was formatted by diskmanagementd (1412.11.7) and last modified by apfs_kext (1412.41.1).
** Checking the object map.
** Checking the snapshot metadata tree.
** Checking the snapshot metadata.
** Checking the extent ref tree.
** Checking the fsroot tree.
** Verifying allocated space.
** The volume /dev/rdisk1 appears to be OK.
Is there a work around for this? a config file that can be edited to make bootcamp assistant disregard checking if there's a second drive in the system? How could a totally unrelated second internal drive somehow make running bootcamp assistant not possible?
Thanks for this reply the more info the better. Because I consider myself a power user and don't mind having to re-format drives and reinstall mac os as required, I would be very interested in how to work around this. Somewhere in the code there must be conditions stating macprox,x is support for two disks, one dedicated to windows. I would like to know where this is and insert my iMac18,3 in its place and see what happens. Are you able to point me in the right direction?
Failing that I will have to try opening up the iMac again, unplugging the main NVMe MacOS drive, boot up the second ssd and recover Mac OS, run boot camp, get windows going, clone this disk to another drive, reformat and reclone so that windows now has the whole drive, reinstall the original mac os nvme drive, then seal it all back up again!
You have two internal disks in a non-Fusion configuration on an iMac. This is an unsupported configuration for Bootcamp Assistant, even though macOS will work.
Tumbles1982 wrote:
Thanks for your efforts so far.
Done. https://discussions.apple.com/thread/250931609.
Responded on your new discussion.
Unfortunately, it didn't help...
From macOS Terminal, post the output of
sudo fsck_apfs -n -l /dev/rdisk1 (if you do not have a Fusion drive)
or
sudo fsck_apfs -n -l /dev/rdisk2 (if you have a Fusion drive)
This looks clean. Can you post the output of
diskutil list
diskutil apfs list
thank you for info...
Was the hardware on this iMac modified from it's original configuration?
It would make sense to start a new discussion. Can you post the current state of the disks in the new discussion? Run
diskutil list
diskutil apfs list
Boot Camp internal error
