Apple - virtualbox installation failed on macOS Catalina
To install and/or use virtualbox you may need to enable its kernel extension in: System Preferences → Security & Privacy → General
For more information please refer the documentation or this Apple Technical Note: https://developer.apple.com/library/content/technotes/tn2459/_index.html
If you've used Migration Assistant
I'd moved from an old machine running macOS Mojave to a new machine using macOS Catalina using Migration Assistant. This bypassed the normal installation process, so the Security & Privacy System Preference never displayed a prompt that would allow me to grant VirtualBox permission to run.
The solution was to download the latest, Catalina-compatable VirtualBox installer
.dmg (version 6.12 and up) and run
VirtualBox_Uninstall.tool. This failed, but prompted for extra permissions in System Preferences... Security & Privacy. After I granted permission to the uninstall tool, I ran the Uninstall tool again successfully.
I then ran the VirutalBox install
.pkg, which will failed. VirtualBox did install, just not completely. I then launched VirtualBox, which failed, but gave me a prompt in System Preferences... Security & Privacy that allowed me to grant permission for VirtualBox to run. I then launched VirtualBox again, and was good to go.
For Catalina you'll need to do this:
Restart your mac in Recovery mode (cmd + R)
Then open a Terminal and enter: spctl kext-consent add VB5E2TV963
Restart your mac.
VB5E2TV963 is the code for oracle.
(Taken from https://forums.virtualbox.org/viewtopic.php?f=8&t=93133 )
For me was the only way to install it.