I have a microSD card that I use in my phone. It shows up in OSX as read-only, with no option to change that in Get Info and no ability to erase/re-format it in Disk Utility. Formatting it on my phone is also not an option, as the phone does not appear to have the ability to format a card. I know the card isn't locked, and the card reader functions normally with other SD cards. This problem hasn't always existed, either; when I first got the phone, everything worked just fine. The big problem is that there are some music files on this card that the phone doesn't recognize (and therefore won't delete), and I can't get rid of them on the computer either. They're just sitting there, taking up space. So basically: Is there any way to hack the permissions on this card so I can delete those files? EDIT: Stuck the card and its adapter in my camera and formatted it. The music files are now gone, but the read-only problem persists.