Could this be because I don't have enough space? It did say that I'll have 10GB left if I do this partition.
Hi, I had this problem, my issue was I was using Time Machine and I needed to delete the snapshots which are saved locally.Is says "An error occurred while partitioning the disk. Please run Disk Utility to check and fix the error."
And it still says that even after I ran disk utility.
I’d imagine the beta isn’t 100% stable and may be giving you issues in that respect. The reason I installed boot camp was to move away from Parallels on one of my iMacs, a 2013 i7 maxed out. The performance was slow, and crashed every so often, which might be ok for some but it ended up costing lost work hours, the disk check after a crashed session can take upwards of 2 hours. Conversely I have a maxed out 2017 iMac i7which runs parallels just fine, but their forums are full of people with the same issue I have with the 2013 iMac, seems to be luck of the draw.im also having the same issue, have tried first aid multiple times, turned off time machine, used tmutil command as mentioned above and still get the same error. I wonder if this is just something to do with me running Big Sur Beta. I've spent a few hrs on this already that im getting to the point of just buying Parallels and calling it a day.