Sorry guys, only just seeing your responses. In regards to the notion of the OS needing to be re-installed, I didn't have to. As far as I'm concerned with the RAID-1, there was one failed disc and the other was simply "poorly" or "ill" - it hadn't actually failed. The man from Dell Tech Support diagnosed it as "failed" even though it was still working and thus recommended its replacement. I think his diagnosis of the other two (HDD 6 & 7) proved accurate when HDD7 failed during the rebuild of HDD6. LUCKILY, I have suffered no data loss nor have I had to rebuild the OS on the server