I was running through the various options of Produce when Explorer went into a crash/restart loop that persisted through a reboot. It was a conflict between Explorer and one of the files I'd produced. (Since I'd produced them to the desktop, I couldn't keep Explorer away from them.)

I got rid of all of those files and the problem went away. I'm not sure which format it was that caused the problem, but I think it was MKV. Right now I don't have time to track it down, but I figured I share my experience in case someone else gets into such a pickle. If Explorer crashes when you look at the folder you produced into, either blow away the entire folder or boot into safe mode and use the console to delete the problematic file. Jerry Schwartz