If you are having trouble approving the kernel extension for Microsoft NTFS for Mac by Tuxera, you can try the following..
- Restart macOS to Recovery mode: https://support.apple.com/en-gb/HT201314
- Unlock boot drive by mounting it in Disk Utility (found in Utilities menu)
- Select Terminal from Utilities menu after mounting the drive.
- In Terminal.app input, type following and press return/enter:
(where volume name is usually 'Macintosh HD') for example:
chroot /Volumes/'Macintosh HD'
- After this type in the next command
spctl kext-consent add PPNVCC9Z68
- Reboot normally
PPNVCC9Z68 is our Team ID the system extension has been signed with it. This adds our kernel extension to a list of approved extensions and should allow it to load.