"Add spare" on N5200 doesn't work

Update: RAID 5 has gone from degraded (dropped one disk) to damaged (dropped second disk while rebuilding). See below.

Hi,

My N5200 became degraded today while trying to copy a large file. It has 5 identical 500gb drives, and the 1st drive has dropped out of the RAID 5 array. I've tried removing and reinserting the 1st drive several times, but the RAID does not start to rebuild. I've tried forcing it manually several times via the web interface, i.e. N5200>Storage>RAID>RAID Config>Check "Spare" and click "Add spare.">Click OK to confirm. This gives a message that "RAID Setting Successfully! All current active services will be stopped when RAID is being created" but the RAID still does not start to rebuild. Clicking OK at the "RAID setting successfully" message takes me back to the RAID page, which still shows Status: Degraded and no signs that the RAID is rebuilding.

I've also tried rebooting and repeating the above steps. How do add back the disk? Rebuilding the RAID from scratch is not an option as I have nowhere to store the data during the rebuild. This is my sixth time posting here for help in 18 months so I'm getting really annoyed with this thing.

Edit - After rebooting and clicking "add spare" for the fifth time it started to rebuild.

I sure wouldn't use a drive that dropped out and ignore restart commands for any length of time at all.

****. As it was trying to rebuild, the third drive died. It starting beeping and the web interface said the RAID is now "damaged" and I should turn it off. It is currently off. It was on a UPS so I don't think this was a power issue.

First, how do I recover my data? The N5200 has firmware v2.00.08. I have the SYSUSER module installed so I might be able to SSH in if I turn it back on.

Secondly, should I buy a new NAS or would replacing the drives be enough? The drives are all Western Digital RAID editions, models WD5000YS and WD5000ABYS. Based on what I just read elsewhere, the drives might still work, but were dropped from the array due to incompatibility issues for those particular drives.

Perhaps someone could at least tell me whether it is safe to pull out the drives and make disk images that I could try to recover from? Would the N5200 even "know" if I removed the drives, copied them, and put them back one by one?

if that would happen to me... i would try doing a disk image (in dos or even lower OS) of one drive at a time onto a larger drive, ie.. 500-->750, just to make sure there was no disk size issue. then after doing all 5 drives keeping them all numbered in the same sequence i'd put them back in and boot. then i'd just hope the thecus can read the drive data. in theory, it should work... but no guarantees.

I'm still working on making the drive images, as I'll need to go buy a bunch of hard drives and external enclosures to do the transfer. I'd really like to hear what the Thecus people have to say about recovering the data...