I have installed Ubuntu Desktop x64 12.01.1 as guest in VirtualBox.
When I installed VirtualBox Guest Additions, Unity desktop (top bar and left program icons bar) becomes invisible. The problem was found in VirtualBox 4.1.20 and still exist in 4.1.22.
Reinstalling doesn't help. Maybe someone knows how to overcome this issue?
Host Os: Windows 7 x64
Host video driver: Intel Video Driver 18.104.22.168.13(latest)
Video: embedded into Intel Q45