My windows installation had been stonewalled by error;
Windows cannot locate the disk and partition specified in the unattend answer file’s <ImageInstall> setting. Make sure the setting references a valid partitition and restart the installation
Current OS: 10.5.7 Catalina
MacBook Pro with Touch Bar
I'll chime in because I was just having the same issue as you on an iMac Pro that I just received. Out of the box it was running Catalina so I created an admin user and installed Big Sur immediately. I copied the Win10_20H2_v2_English_x64.iso to the desktop, ran Boot Camp Assistant, and got hit with the error you quoted. I deleted and recreated the BC partition a few times but it had no effect. Suspecting a partition map issue (and since I had no data on the iMac yet) I booted to Recovery (Command (⌘)-R) and wiped out the entire partition before reinstalling a fresh, clean copy of Big Sur. After that the problem vanished. Your milage may vary as you likely have data to preserve, but it's worth considering making a backup and starting from a fresh partition. Best of luck!
MD5=10d50d88fac6306a00ddb41e983a046b
No mounted disk images
Both Catalina and Big Sur have issues with BC Assistant. There are significant APFS (filesystem) differences between Catalina and Big Sur.
Did you accidentally mark this as solved?
Sorry. I accidentally marked it as solved.
Yes. Done
Excellent!
Thanks for the help!
Bootcamp: Windows cannot locate the disk and partition
