I want to copy my some files from Mac (Macbook-Air) to a USB external hard drive, formatted as NTFS.
How is it possible? Because when I do copy my files from the Mac and go to paste them on the external HD there is no option for paste.
The problem is that your drive is NTFS formatted. OS X can't write NTFS out of the box (at least not without some tweaks). Here are some ways to do this.
Format the drive as FAT-32
This is the obvious answer to those who don't want to install software that potentially could harm their data (which is always the case with hacks / unstable software). Re-format the drive to FAT-32, which both Windows and OS X can read and write out of the box.
This is of course not a solution for files larger than 4GiB.
NTFS-3G via Homebrew installation
If you have Homebrew, installing NTFS support is as easy as running the following in a terminal:
Then, follow the instructions on the screen. Homebrew will tell you how to replace the default OS X automounter so external NTFS drives are mounted using the new driver. Those are a couple of commands you need to run through your terminal.
NTFS-3G via GUI installation
This is a free version (there's also a paid one, and the free one's a bit harder to find).
These are not free, but offer support and promise better speed/stability.
Related Super User questions
I felt those were lacking an overview of tools:
Get the latest version of MacFuse first from here.
After you install it, you will need to install ntfs-3g. This is the FUSE. You will need to make sure you have the latest versions of both, since older versions of ntfs-3g might not work with a newer version of MacFuse.
You should now be able to read AND write from your Mac to any NTFS drive.
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