Enabling print screen for VM VirtualBox windows on Windows 7

I was trying to document a VM VirtualBox installation with screenshots, but I noticed that I couldn’t make screen shots of active VM VirtualBox windows using ALT-Print Screen. This is on Windows 7 64-bit, version of VirtualBox is 4.1.10.

I first thought there was something wrong with my keyboard or Windows settings, but making print screens of other windows DID work. Then I found this: http://superuser.com/questions/66353/print-screen-doesnt-work-if-virtualbox-is-active-window.

So, to enable print screens of active VirtualBox windows, you need to uncheck “Auto Capture Keyboard” under File -> Preferences -> Input. After this all worked fine!