Recently we've had a few questions and forum posts concerning ArcGIS Explorer and Windows Vista. Please remember that ArcGIS Explorer is not currently certified for Windows Vista, but we'll be doing this soon. 

If you've been experimenting with Vista already, one thing you may have noticed is that navigation is sluggish. Turning off the background stars usually resolves this. To turn off stars, go to File > Map Properties  and then choose Effects > Environment. You'll see the checkbox for stars, and other environment options.