package virtualbox-guest-dkms 6.1.16-dfsg-6~ubuntu1.20.04.2 failed to install/upgrade: installed virtualbox-guest-dkms package post-installation script subprocess returned error exit status 10

Kernel 5.12.0-051200rc7-generic

I had a similar problem with the Nvidia dkms package, which I think was also related to the kernel version. I can't remember how I was able to overcome it.

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: virtualbox-guest-dkms 6.1.16-dfsg-6~ubuntu1.20.04.2
Uname: Linux 5.12.0-051200rc7-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.17
AptOrdering:
 virtualbox-guest-dkms:amd64: Install
 virtualbox-guest-utils:amd64: Install
 virtualbox-guest-x11:amd64: Install
 NULL: ConfigurePending
Architecture: amd64
CasperMD5CheckResult: skip
Date: Mon May 24 17:16:38 2021
ErrorMessage: installed virtualbox-guest-dkms package post-installation script subprocess returned error exit status 10
InstallationDate: Installed on 2021-04-13 (41 days ago)
InstallationMedia: Ubuntu 20.04.2.0 LTS "Focal Fossa" - Release amd64 (20210209.1)
PackageArchitecture: all
Python3Details: /usr/bin/python3.8, Python 3.8.10, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.5
SourcePackage: virtualbox
Title: package virtualbox-guest-dkms 6.1.16-dfsg-6~ubuntu1.20.04.2 failed to install/upgrade: installed virtualbox-guest-dkms package post-installation script subprocess returned error exit status 10
UpgradeStatus: No upgrade log present (probably fresh install)