Question: I have Ubuntu 12.04 installed on my machine. I also installed Virtualbox so that I can run windows 7.

I set my virtual box with 4 GB RAM and 25 GB virtual HDD and after I press Start, it doesnt boot from the windows dvd in the optical drive, but instead i get this error:

Failed to open a session for the virtual machine win7.

```
VT-x features locked or unavailable in MSR. (VERR_VMX_MSR_LOCKED_OR_DISABLED).

Result Code: NS_ERROR_FAILURE (0x80004005)
Component: Console
Interface: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}

```

Do you have any idea what is it and how I could overcome this?

Thank you!

Answer: 
This behavior has now gone in Precise after an upgrade (I admit, I experienced that problem too). I suggest you to upgrade your machines. May be that was a bug

```
sudo apt-get update
sudo apt-get upgrade

```
Your monitors won't be damaged from lack of screensaver :D

1. To set timed screen turn off with lock enter System Settings -> Brightness and Lock.
2. Set "Turn screen off when inactive for:"
3. Set "Lock" to ON
4. Set "Lock screen after:" to "Screen turns off"