The FBI doesn't and never did work that way. There are also FBI telephone scams wanting people to wire money to pay fines. Never send money this way. If the government wants you, they come to your door. These should be reported to proper authorities but never respond to any such message in any way shape or form.
My friend doesnt download music but got a window that said the FBI locked his computer down & to send $200.00 on a Gren Dot Card. Also there was misspelling in the warning, is this for real