Does eating Danish butter, purchased without knowledge of its source, constitute consuming something unlawful (haram)?

It is permissible for a Muslim to use what he owns of the property of disbelievers, unless it is Haram (definition) in itself. Thus, there is no sin in eating the mentioned butter if it is made from a permissible substance, and there is no sin in buying it as long as you bought it without knowing that it is from the products of the countries whose economy scholars have called to boycott.