How to install Guest addition in Mac OS as guest and Windows machine as host

Question

I am trying to copy contents from my host machine to a guest machine, but for copying I need to install the Guest additions disk.

Or there is there another way to access host machine content on the guest machine or vice-versa?

Answer 1

Guest Additions are available for MacOS starting with VirtualBox 6.0.

Installing:

1. Boot & login into your guest macOS.
2. In VirtualBox UI, use menu Devices | Insert Guest Additions CD image...
3. CD will appear on your macOS desktop, open it.
4. Run VBoxDarwinAdditions.pkg.
5. Go through installer, it's mostly about clicking Next.
6. At some step, macOS will be asking about permissions for Oracle. Click the button to go to System Preferences and allow it.
7. If you forgot/misclicked in step 6, go to macOS System Preferences | Security & Privacy | General. In the bottom, there will be a question to allow permissions for Oracle. Allow it.

Troubleshooting

1. macOS 10.15 introduced new code signing requirements; Guest additions installation will fail. However, if you reboot and apply step 7 from list above, shared clipboard will still work.
2. VirtualBox < 6.0.12 has a bug where Guest Additions service doesn't start. Use newer VirtualBox.