SD card is read-only, all Disk Utility options grayed out I'm using Lion (10.7.3) on a mid-2010 MacBook Pro. I just got a 32GB SD card and formatted it with my camera. I'd like to transfer some files onto it from my computer, but the card seems to be read-only when I access it in Finder. And in Disk Utility, all options are grayed out so I can't reformat the card.





I found this KB article which seems to describe the problem, but the solution doesn't work:

$ diskutil partitiondisk disk1 JHFS+ newdisk 100%
Started partitioning on disk1
Unmounting disk
Error: -69877: Couldn't open device


What's going on and how can I get around it?

Edit: yes, I already checked the physical lock switch on the card!
I was just going to suggest the lock switch too... but if that's not it, can you click the Partition tab and tell us how the card is currently formatted?  If I remember right, OS X can read but not write an NTFS-formatted device, but it seems unlikely that your camera would have formatted the card that way.