Write to an NTFS drive on a Mac

macOS lets you copy files off an NTFS drive but not onto it. Here is why, and what to do about it.

What NTFS is

NTFS is the filesystem Windows uses, both for its own drive and for external drives formatted on a PC. A USB drive formatted on a Windows machine is usually NTFS.

The other common one is exFAT, used by most memory cards and many USB sticks because Windows and macOS can both write to it. If your drive is exFAT then macOS already handles it and none of this applies. To check, click the drive in Finder and choose File, then Get Info. The Format line tells you.

What happens when you plug one into a Mac

The drive appears in Finder and you can see the files. Copying files off it works normally. Copying anything onto it does not: Finder refuses, and the drive behaves as though it were locked.

macOS opens NTFS drives read-only. It has been able to write NTFS for years, but that is switched off and there is no supported way to turn it on. Writing NTFS is harder than reading it, and a mistake can leave a drive that Windows then refuses to open.

How Lukotta writes to it

Lukotta opens the drive with the NTFS driver from Linux, which does write, and which Linux machines use every day. The drive is handed to Finder afterwards, so copying files onto it works like copying anything else.

The drive stays NTFS, and Windows reads it afterwards.

Opening the drive

1. Plug in the drive. Lukotta lists it.
2. Click it.
3. It appears in Finder under Locations, and files copy in both directions.

An NTFS drive usually has no password, so there is nothing to type unless BitLocker has been turned on as well.

Drives Windows did not shut down properly

Windows marks a drive as dirty when writing was interrupted, usually because the drive was unplugged or the machine lost power partway through. The mark warns the next computer that opens it that the drive may be half-written and should be checked.

Fast Startup leaves the same mark even when nothing has gone wrong. It is on by default in Windows 10 and 11. Instead of shutting the machine down it hibernates it, which leaves the drive looking as though it is still in use.

macOS refuses a drive in either state and gives no reason. Lukotta opens it.

If you still have the Windows machine, the tidier fix is to plug the drive back in and shut that machine down properly: hold Shift as you click Shut down, which skips Fast Startup.