iOS iPad Launch Images are corrupt

I replaced all the Portrait Launch Images in the Project Settings with custom Images. I used the same Size, DPI, Colorsettings (Space and profile) as the default ones in the engine.
Left: Default Launchscreen
Right: My own custom one

When I load in all the custom ones for the iPads then I receive following message from the App Store:

This happens only when I try to load in the ones for the iPads. All iPhone Launchscreens work fine.
I tried to replace the default ones in the Engine with my custom ones by giving them the same name but without success. I receive the same Error.
I tried it for every iPad Launch Image and I got the same Error as above referencing to that Image.

A year ago I was always able to set the Launchscreens for iPhone and iPad without an Error.

What image software did you use? Try exporting new files.
If you used one of the many free online services that scale icons, many of them give bad results. One that worked fine is

I used Gimp to scale and export all my icons and launch screens. I did the same procedure with all of them and they work all except the iPad launch screens.
The Error report of the App Store isn’t very helpful either.
“The Image File appears to be corrupt”
The software you mentioned is only scaling icons and not launch screens.
Anyway thank you for the answer!