Installing guest additions on Xubuntu guest

Question

Iam failing to install guest additions on a Xubuntu 17.10 guest, hosted on a Xubuntu 16.04.

I started the host, clicked devices, insert guest addition cd, the iso was downloaded on my host, then inserted as CD for the guest. Then I run sudo ./VBoxLinuxAdditions.run and I get the following error output:

myuser@myuser-VirtualBox:/media/myuser/VBOXADDITIONS_5.0.40_115130$ sudo ./VBoxLinuxAdditions.run 
[sudo] password for myuser: 
Verifying archive integrity... All good.
Uncompressing VirtualBox 5.0.40 Guest Additions for Linux............
VirtualBox Guest Additions installer
You appear to have a version of the VBoxGuestAdditions software
on your system which was installed from a different source or using a
different type of installer.  If you installed it from a package from your
Linux distribution or if it is a default part of the system then we strongly
recommend that you cancel this installation and remove it properly before
installing this version.  If this is simply an older or a damaged
installation you may safely proceed.

Do you wish to continue anyway? [yes or no]
yes
Removing existing VirtualBox DKMS kernel modules ...done.
Removing existing VirtualBox non-DKMS kernel modules ...done.
update-initramfs: Generating /boot/initrd.img-4.13.0-16-generic
update-initramfs: Generating /boot/initrd.img-4.13.0-17-generic
grep: /opt/VBoxGuestAdditions-*/init/*: No such file or directory
Copying additional installer modules ...
Installing additional modules ...
Removing existing VirtualBox DKMS kernel modules ...done.
Removing existing VirtualBox non-DKMS kernel modules ...done.
Building the VirtualBox Guest Additions kernel modules
The headers for the current running kernel were not found. If the following
module compilation fails then this could be the reason.

Building the main Guest Additions module ...fail!
(Look at /var/log/vboxadd-install.log to find out what went wrong)
Doing non-kernel setup of the Guest Additions ...done.

Thats why I try to install the headers for the current kernel:

ruby@ruby-VirtualBox:/media/myuser/VBOXADDITIONS_5.0.40_115130$ sudo apt-get install linux-headers-$(uname -r)
Reading package lists... Done
Building dependency tree       
Reading state information... Done
linux-headers-4.13.0-17-generic is already the newest version (4.13.0-17.20).
linux-headers-4.13.0-17-generic set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 5 not upgraded.

But they are already up to date, so whats the problem here? I also dont understand, what this You appear to have a version of the VBoxGuestAdditions software on your system is from. Until now I only installed virtualbox-guest-dkms. Is that possibly a problem?

Solution

so, the problem was indeed, that the kernel in the guest was newer than in the host. I don't know how to really solve this, but i just installed Xubuntu 16.04 in virtual box and then it worked well.

Comments

[Jeno]

it looks like the problem is, that the kernel on the guest system is newer than on the host system..