Finally had to upgrade one of our development machines to Silverlight 2 Beta 2, and boy did Blend not like it. After installing Beta 2 the project opened in Blend but crashed when you tried to build the project. So uninstalled Blend, installed the latest version and tried again. This time the browser launched but there was an error (from javascript) and an empty page. After some messing around I finally threw my hands in the air and just created a brand new project and copied the assets over. That didn’t work either. The new project had a different name and after trying seemingly everything (I’m not a Blend person) I gave up and created yet another project but this time was careful to give it exactly the same name. Finally the project runs. I thought we could have at least had an upgrade old project, oh well that’s the life of a beta user I guess.