A very strange thing is happening to me. I have a DMG .spareimage encoded with pasword. I can open it because I remember the password, but I can not make changes because it is locked in writing as in the icon on the bottom left. It seems that this has happened since: - I had the DMG protected by a special command in the Get Info window - I opened the DMG with the correct password - realizing that the DMG was locked in writing, without expelling the volume, from Finder I removed the protection from Get Info but nothing to do, the volume remains only reading. It was useless to eject the volume, reopen it, unlock it, relock it. Nothing! What should I do?