drive boot up: error occured

Hello,
My pc has 4 harddrives installed: c:windows, d:data (raid 0/ two identical drives), e:music. Now recently when I start my pc during bootup when the pc is checking all the devices and drives it shows ‘error occured!’ on the second drive of my raid 0, all the others are ‘ready’.
I tried chkdsk but this doesn’t show any problems.
Any suggestions?