Hi if it said RECERTIFIED then that could mean a few things .
1: The drive may have been sold to someone and they did not want it and returned some A+ tech checked it out and said it was OK.
2: The drives are actually recertified and have been returned fixed and put out for sale.
I would first of all go check the warranty on the drive. You can do that here. http://support.wd.com/warranty/index_end.asp?lang=en .
Personally If it said recertified and it was me I would send those drives back. The problem of customers returning drives when they can’t get them to work you don’t know what they have done to them dropped on the floor plugged in wrong. I would not take the chance. But a recertified drive would not have the same warranty as a new one.