Thank you for answering.
As the title says, error is version: 8.81
Videos downloaded with: IDM, 4K Video Downloader, aTube Catcher, YouTubeByClick. I add the videos to the VP and when exporting them without loss the error appears.
With version 8.51 there is no such error.
The videos do not have any errors nor the movies. It is VideoPad 8.81 that has the error. I repeat version 8.51 does not have that problem.