The "Advanced : Disks" page displays Disk configuration : RAID 5 (Normal) because the Storage synchronization completed.
From your system log page it looks like a disk error occured during the synchronization. The failure could be a bad sector on a second disk that contained parity or data for the array. That would mean you had a two drive failure (the original disk and the second disk with the disk error). Unfortunately a two disk failure in a RAID 5 array is unrecoverable.
I have a backup of a big part of my data. In fact I lost the data in transit, recorded on the SS4000 for a short time before definitive storage (because of lack of space on my computer). Bad luck, in the meanwhile the disk 3 failed!
I understand I have a second disk with bad sector. Of course with two errors my data cannot be recovered.
I have the faulty disk (number 3). It makes a clic noise at starting and finally fails to start. Maybe a mecanical problem.
Suppose one moment that disk 3 is repaired without loss of data: if I replace this disk 3 at position 3 of the SS4000-E, the system come back to its previous state, that is to say one error somewhere on disk 1, 2 or 4. But in RAID 5 configuration, data are available with only one error. In this case, how will react the SS4000-E viewing the original disk 3 (readable)? Is it a way to retrieve my data (if disk 3 is repaired)?