replacing failed hard drive

Ok I put the new disk in, nothing changed so I closed the frontview webpage and shut off the readynas, then turned the readynas back on. The led message on the front of the readynas still flashed "Vol C degraded" along with some other message about drive 2 indicating the drive was not working, which I think I've seen before but can't remember what it was right now...so it appeared to me that nothing had changed and so I opened up frontview and nothing changed there also, just showing me the drive was dead...except now that I think about it, I'm pretty sure there was no longer an X over the number 2 position on front of the readynas. Then a bit later I saw a different message on the front of the readynas, which was "vol c unprotected", which gave me some hope of something different happening, then a bit later I saw some resync message on the front of the readynas, and at this time the number 2 position is flashing with the message Resync C: 2.6%. So it appears to be working. Frontview still shows Disk 2 as dead with the temp at 0 C / 32 F, but at the bottom of the frontview "Health" page, instead of just having a solid amber light beside the word "Disk", the light is flashing from green to amber and also is flashing the same beside the word "Volume".

Now I guess I will put the defective drive in a USB external enclosure and run windows checkdisk on it. Perhaps there are just some defective clusters which can be fixed...if not then I will take the drive back to where I bought it and ask about the warranty. Also just now in frontview I clicked on "Logs" and I see a few good messages, "system is up", then "Data volume will be rebuilt with disk 2", then "RAID sync started on volume C. Thanks again for the speedy help!