No Mountable File System In MacBook can create trouble for the Mac users and no disk image file that is .dmg file will get mounted in the Mac drive. It is necessary to mount the image file if you want to install any software in the system. You can check by mounting other image files if they get mounted then the problem is with that specific file and you can try to get a fresh copy of the image file. If No Mountable File System In MacBook error is shown with all the files then the problem can be with the drive. You can use the disk utility to scan for the problem in the drive and fix it. If the problem is not solved then you need to format the drive to fix No Mountable File System In MacBook. If you have lost any data from the drive then use the time machine backup to restore all the files. IF the backup is not available or it can not be completed then you can use the Mac data recovery software to restore all the files in an easy and effective way. So you should first fix No Mountable File System In MacBook and then use the recommended recovery tool.