In the item list I no view images, but I don't see any option to block them.
In the categories, under "Item view options in category listings" the option "Image" is "Show".
There are not heredity of other category
In the Menu all the option are "grey", not selectable.

I don't understand where I must look.

Thanks in advance
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I've understood.
If there is a value in the field "Introtext word limit" the image has not displayed. :blink:

The word limit function needs to strip all the HTML, otherwise it may break your site. That's why image is stripped. You can use the "Item image" tab to upload images.