Virtualbox issues after upgrading from 14.04 to 14.10

[open2linux]

Thanks d-koroliov and thomas-toem for your help. But still I can not make virtualbox works.
Windows7 begins the starting process but it aborts and goes back to the virtualbox main screen.
I get this error message:

-----------------------------
There is no virtual machine with the identifier f4a630af-29ae-401f-8968-48f687a51d70.
Could not find a registered machine with UUID {f4a630af-29ae-401f-8968-48f687a51d70}.
Result Code:
VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)
Component:
VirtualBox
Interface:
IVirtualBox {fafa4e17-1ee2-4905-a10e-fe7c18bf5554}Screenshot starting.jpgScreenshot settings.jpgScreenshot vsettings.jpgScreenshot starting.jpgScreenshot settings.jpgScreenshot vsettings.jpg

-------------------
And in the settings page it doesn apperas any Extensions.
Enclosed the screenshots.
(I don know why the duplicated images, sorry for that)

[impliedconsent2]

To solve this one needs to remove an old extension pack (and may be install a new one), this can be done in the file->preferences->extensions menu (or just press Ctrl+G and select the "extensions" tab).

Just download the extension pack and add it. It will automatically upgrade the old version to the new version.

[open2linux]

Solved.
After removing an old extension pack and I disabling the usb controller it works.
Thanks!

[slickymaster]

Moved to the Virtualisation sub-forum

[Joakim_Lindbom]

Removing the ExtPack (and reinstalling VirtualBox) didn't do the trick - but a variation did:

sudo VBoxManage extpack uninstall "Oracle VM VirtualBox Extension Pack"
wget http://dlc-cdn.sun.com/virtualbox/4.3.18/Oracle_VM_VirtualBox_Extension_Pack-4.3.18-96516.vbox-extpack
sudo VBoxManage extpack install Oracle_VM_VirtualBox_Extension_Pack-4.3.18-96516.vbox-extpack

Now all seems to be working fine.

[lukastojanovicbg]

Thanks! You saved my day.