[Solved] Problem starting VMs after Yosemite

[Per Steffensen]

VirtualBox 4.2.4 r81684. It is a long time since I updated my VirtualBox, but when I run "Check for updates ..." is says that I already am running the most recent version of VirtualBox

I believe this problem started after I upgraded from Mavericks to Yosemite. I used to be able to start my VMs fine. Now they will not start. E.g. when I try to start my VM "Win XP" I quickly get the following error-message
---- error msg ----------
Failed to open a session for the virtual machine Win XP.

The virtual machine 'Win XP' has terminated unexpectedly during startup with exit code 1.

Result Code: NS_ERROR_FAILURE (0x80004005)
Component: Machine
Interface: IMachine {22781af3-1c96-4126-9edf-67a020e0e858}
----------------------------

In another popup window I see this error-message
---- error msg ----------
Kernel driver not installed (rc=-1908)

Make sure the kernel module has been loaded successfully.
----------------------------

The same problem exists for all of my VMs. I have a few Ubuntu VMs also.

What can be wrong? What can I do?

Regards, Per Steffensen

[loukingjr]

The latest version of VB is 4.3.18. Here: https://www.virtualbox.org/wiki/Downloads
Make sure to update the extension pack and install the guest additions. You should use the VirtualBox_Uninstall.tool to remove your outdated version first.

[Per Steffensen]

Ok, I will try 4.3.18

Should I just use the trunk-version of VirtualBox_Uninstall.tool (wwwdotvirtualboxdotorg/svn/vbox/trunk/src/VBox/Installer/darwin/DiskImage/VirtualBox_Uninstall.tool), or do I need a certain revision in order to uninstall 4.2.4?
How to export/import my existing VMs?

[Per Steffensen]

I did the following
* Uninstalled 4.2.4 using trunk version of VirtualBox_Uninstall.tool
* Installed 4.3.18 including extension pack

Now everything works. I can start my VMs again.

Thanks alot!

[loukingjr]

I did the following
* Uninstalled 4.2.4 using trunk version of VirtualBox_Uninstall.tool
* Installed 4.3.18 including extension pack

Now everything works. I can start my VMs again.

Thanks alot!

welcome.

[loukingjr]

if you could mark this thread as solved. Just go to the first post>edit>type [Solved] in front of the title>submit.