So it will interest you to know that running Virtual PC 2004 under the February CTP release of Windows Vista is a much nicer experience than it has been in prior builds of Windows Vista. For one thing – networking is now completely functional. In fact there are only two issues with running Virtual PC under the February CTP release of Windows Vista:
- Desktop composition will be disabled while running virtual machines
Desktop composition (also known as ‘Glass’) is what gives you all the cool 3D desktop stuff under Windows Vista. Unfortunately desktop composition requires that all video data be written to an offscreen buffer and then composited through its 3D engine. Virtual PC uses DirectDraw – which locks the physical display and draws directly to it. When this happens – desktop composition is disabled. Normally this is not a problem – as most DirectDraw applications run in fullscreen mode – so you do not notice. This is something that we are going to need to change in Virtual PC in order to be fully compatible with Windows Vista.
- With desktop composition disabled, moving an active virtual machine will result in corrupted graphics until the virtual machine updates its display
This is a bug in Windows Vista – but it is fairly easy to deal with.