WD Netcenter power light flashing amber and cannot access data

When I try to turn up my WD500B019 NAS disc amber led turn into flashing amber and blu but not become blu and I cannot access the disc. I connect the disc (it’s a SATA) to my computer but I don’t know the filesystem. WHat data recovery sooftware I should use? Even if I manage to recover my data, how should I format it? Could I change it with another disc?