If it has two, you’d need to change it to one. Make sure your external drive has a one word name.

Finally reboot your Macbook before performing this to avoid any unforeseen conflicts. I only did this on my 1TB and 2TB Western Digital external portable hard drives. Also I did not try this on my Bootcamp partition as I wasn’t in the mood for surprises. It was completely formatted with Yosemite. NOTE: I did this on a Macbook Pro Retina with a fresh install of Mac OS Yosemite i.e the machine wasn’t upgraded from Mavericks to Yosemite. The process is quite simple and flawless but as always you’re advised to backup your Macbook before proceeding should in case something goes wrong and results in data loss. While there are third party apps out there that can enable this function, they are somewhat of pricey thus my glee when last night I discovered that you could actually write to NTFS partitions on Mac OS X by just editing a simple file called fstab. Mac OS X by default doesn’t allow you to edit files on NTFS formatted drives be it an internal NTFS partition or an external USB flash/hard drive with NTFS format.

Open ntfs on mac in read write