This has been asked before but I can't find the solution now. The solution was something about going into blender render, setting the bake type to vertex colors and then just baking but I'm just getting pure white bake. Obviously I'm missing some steps... or something. I do most of my work in cycles so I think the issue could be something to do with the nodes. Do the nodes or materials need to be set up in certain way?
Baking vertex colors has been working just fine before. I just did this a couple of days ago but something has now changed and I can't get any my vertex colors to bake anymore. I just get white.