How to fix the error: Data file not loaded and not selected. Loading is not possible?

Question

1C-Bitrix

On one site I do a standard unloading of the infoblock in csv.
On the other I try to fill it.
I get the error "The data file is not loaded and is not selected. Loading is not possible."
Although the file is naturally selected.
Who faced or can know how to solve?

Answer 1

Similar problem. I suspect that perhaps the site where the file is imported does not have some of the custom properties that the second site has.