It means that the ID doesn't exist and the only BOSS data it "pulled" was 00's. If it's a MYS event, you cannot enter the ID into the serial events but instead have to use the "Recieve via Internet" option, which will cycle through events you haven't received before.
I got the shiny bulbasaur by clicking "recieve via Internet." I'll try with another pokemon game though, see if that helps.