Thanks for you answer...but I'm not sure to have understand it all.
I've tried to change what you said but I still have two disks:
When I'm on the linkstation manager.
On home page I can read:
HDD Space UsedRAID Array 1 0.00 GB / 450.64 GB (0.00 %)
but then, when I go to "Disk managment"
it says on the same page:
RAID Array Information
RAID Array 1
RAID Mode: RAID0
Disk Structure: Disk 1, 2
Disk Information
Disk 1: StatusRAID Array 1
total capacity: 244
Disk 2StatusRAID Array 1
total capacity: 244
here is a copy of my screen
Either this is normal and I souldn't worry about or there is something I don't get.
thanks again for your help.