When I'm trying to install Ubuntu 12.04.2 in virtualbox on windows 7 host, it is getting installed. But, after pressing on Restart now button, the virtualbox is not responding and it is getting aborted.
I am using windows 7 professional and virtualbox-4.2.12.
Please help me with this. I'm facing the same problem with ubuntu 13.04 too. I have no other operating systems running in virtualbox