I dont think that its a bad frame because when i play around with visibility then the frame is oke but only for a moment and only in the timeline, not when i try to render it.
it crashes on frame 026 when i scrub in the timeline and when i render it out. I tried you suggestion of updating quicktime but that doesn’t help (i have quicktime pro). I captured video from a dvd into quicktime. I also thought that that might be it but no.