"The disk you inserted is not readable by Mac OS X", is one most catastrophic error message which horrify almost every Mac OS users. This error is mostly caused when there is a problem in the drive you are trying to access. Well, in both the case users hampers their precious data and goes through sever data inaccessibility issue. In such situation every time you try to connect your media with Mac OS the annoying error message the disk you inserted is not readable by Mac OS X, is appears on the screen and ask for formating. But it is very important that you do not go for the formatting as it will cause removal of all your files from that particular drive. The first thing you need to look for is to rescue the data which is stored in corrupted drive. Once the data is restored successfully then you can easily format your drive and fix the disk you inserted is not readable by Mac OS X. In such situation you have two options to restore your files where the first one is to employ any updated backup copy and in case if no backup is available then you should look for the second option which is third party Mac Data Recovery Software. It will safely rescue all your precious files from and corrupted or unrecognized disk and allows you to fix the disk you inserted is not readable by Mac OS X error easily.