This is the 3665th most frequent Korean word.
불법으로
"Illegally."
Here, '불법으로' modifies the verb '판매했다', emphasizing the illegal manner of the action.
그는 물건을 불법으로 판매했다.
He sold items illegally.
In this sentence, '불법으로' modifies '다운로드한 파일', indicating the files were acquired illegally.
불법으로 다운로드한 파일은 사용할 수 없습니다.
Files illegally downloaded cannot be used.
Here, '불법으로' qualifies how the company violated the laws, marking that the violation was illegal.