Lion no mountable file systems error is one of the most common problem for Mac OS X Lion users. Mac uses DMG file to represent the image of all your data stored in hard drive. Thus for accessing your files it is very important that .dmg files mounted properly. But sometimes due to some annoying reasons .dmg files get corrupted. In such situation when users try to access their files on Mac OS X Mountain Lion no mountable file systems error message appears on the screen. However there is no need to worry because with the help of Disk Utility you can fix any kind partial corruption easily. But if the corruption is severe then you will need to format your Mac system in order to fix the corrupted disk image. By formatting the hard drive all the probables related to your Mac OS X Lion system will get fixed including damaged Disk Mounted Graphics. It will resolve Lion no mountable file system error completely. However in order to get your lost files back you will need to use Mac Data Recovery Software. It very efficient and able to recover any lost, formatted, deleted files. It can also rescue files which gets inaccessible due to Lion no mountable file systems error.