I have come upon a Teradata 550 using Engenio arrays. There are a nubmer of failed disks. I have purchased "New in box" same model replacement drives (Seagtate Cheetah ST373455FC). When I replace the drives in the tray, the GUI (Symplicity Storage Managment for Teradata) tells me "Wrong type drive inserted". I assue it's a firmware issure or there is some special way to tell the GUI to initialize the drive (yet that is grayed out in the menu). I have noticed that if I look at the properties of the new drive, it tells me it is ST373455FC (005) while the disks that are functioning show up as ST373455FC-DAP (MS5C).