Every now and then it happens that disk is unreadable error on Mac appears on the screen and cause inaccessibility of all the existing data stored in that particular disk. Generally this type of issue arises when the external hard drive being used on Mac get corrupted due to certain reason and become unreadable. In such situation you will need to fix this disk is unreadable error on Mac completely in order to get back the access of your lost files. If the corruption is minor then it can be fixed easily using disk utility. But in case if the disk is damaged severely then in such situation there is no other option but formatting the entire external hard drive. Now be must be thinking about the data stored on your external drive. Well as far as the matter of your precious files is concern, once the disk is unreadable error on Mac get resolved completely you can easily get them back all your lost files using backup files. You can also use third party Mac Data Recovery Software in order to recover all your formatted files from external hard drive. Hence it is recommended to fix disk is unreadable error on Mac instantly without having a second thought.