When the drive which has lots of data stored becomes unmountable then it can cause lot of worry and it will compel you to search unmountable drive recovery on Mac. There can be several reasons why the drive became unmountable you must first check the connection wire if it is inserted properly, you should also check the permission settings which can inhibit the mounting of the drive. Sometime the drive is unmountable because the file system has been corrupted or the drive is severely infected by virus. You can also try to connect that drive to another Mac system for unmountable drive recovery on Mac. If you have tried everything and still the drive is not mounting then you have to either format the drive or send it to a technician for repairing. In both cases the data will be lose and you have to perform unmountable drive recovery on Mac after it became mountable again. You can recover data using any backup or you can use the Mac data recovery software that will restore all the lost data back in the drive. All the files will be intact and ready for being accessed and edited. The software is very easy to use and has interactive user interface.