Sorry didn't mean to be unappreciative, just getting totally frustrated.
I did try several files but the result is always the same. I even tried a file that previously worked ok.
I'm going to try installing both versions on my old laptop to see if they work on that.
I also checked my version of Java which is the latest available update.
I'm not going to give up yet because when Roxio works it works well so if you have any other suggestions I would be most appreciative.