Are you using an external hard drive on your Mac system? Have you noticed that the contents of hard drive became unwritable? If you are worrying about external hard drive permissions Mac then you have come to the right place. Here you will get aware of this issue and also know about an easy solution to recover the lost data from Mac computers. Well the formatting of external hard drive is making it writable and readable to the Mac computer. Make sure the external hard drive should not be formatted in the NTFS format as this format is only supporting in the Windows computer. Most often the hard drive which are available commercially has already been formatted in the format of FAT32. This makes the had drive compatible with the Windows and Mac both of the computers. The external hard drive permissions Mac is really a critical situation so in this case you need to go through the setting of hard drive and changes the permission for reading and writing. On the other side it is a common issue that the Mac users may face the issue of data loss. So on that case it is advised to take help of Mac data recovery software.