@rich, thank you for the effort. I tried out your suggestions and found no error in the files. Then I tried the portable version of gimp (https://samjcreations.blogspot.com) and the result is the same, error.
This is where I copied the files :
The result files :
I think I must buy a bigger dust bin
This is where I copied the files :
The result files :
I think I must buy a bigger dust bin
