I posted this at Cornucopia but thought I would here as well. Hey Wabe, Thanks for the reply and I did see your other post over at Rendo which I will copy my reply here over there for others as well. What you said makes sense and I did get a response back from John at e-on saying the same thing. "If the non loading files are related to a single scene, maybe something got corrupted at some point. If the corrupted scene was then saved several times, bak files get corrupted too as they correspond to the version just before the latest save operation." Also, I wrote about the rendercow problems and maybe relating to my other problem of files going bad. On updating one of the rendercows Vue said that the updater was corrupted even though one of the other cows updated fine. So I am thinking I had a bad install of V6I on the Mac Pro and it corrupted everything, my scenes and rendercows. Because after I applied the last update to V6I I also had renders that I was rendering in Vue alone hang or freeze. Just too much weird stuff going on at once. So I reinstalled V6I and updated to before the last update since the latest one screwed with my render times somewhat. I'll just wait for another update from e-on before I even try the rendercows. As to that, here is also what John at e-on wrote in case any one is interested: "Hi Randy, We have indeed fixed a major slow down issue regarding polygonal objects due to a recent multithreading crash fix. We are currently rebuilding a new update so this should be sorted out shortly. There was also a recent fix on rendercows autoupdate I think, so upcoming update should sort things out as well." Sounds like good news to me! Thanks again wabe for responding and giving me some things to look into. Best wishes, Randy