Categories cannot be created - they already exist!?

If I want to create new categories, an error message appears: “Category XY already exists”. But I can’t see it anywhere. No matter where I do it. Why? How can I create new categories? Greetings

Can you see the category after closing and restarting eM Client?

No, unfortunately not

I can’t delete many categories. Is it possible to delete all categories again and create new ones?

Are these categories on a Gmail account?

No. There are categories created in the program.

Can you please give a screen shot of your categories like this: