Thanks Billy and GPFrance, your explanations are very useful. I havent sent the file to Rodluck yet, because i want to try to fix things myself first. With your explanations i have some more possible solutions again, but, as I noticed while trying the other suggestions, my computer is simply too old for this work. So what I will do first is buy a new computer, which is something I need anyway. If by then I still have the same problem, i will send the file to Rodluck to see if he can solve it.