I'm quite new at this so I'm hoping that someone can help us to get back on line. FWIW, MOS has already suggested that we rebuild the group. We tried to start things up and got the following: WARNING: cache read a corrupted block gn=1 fn=7008 indblk=0 from disk 9 NOTE: a corrupted block was dumped to /u01/app/asm/diag/asm/+asm/+ASM1/trace/+ASM1_rbal_9624.trc ERROR: cache failed to read gn=1 fn=7008 indblk=0 from disk(s): 9 ORA-15196: invalid ASM block header [kfc.c:9133] [endian_kfbh] [7008] [2147483648] [0 != 1] System State dumped to trace file /u01/app/asm/diag/asm/+asm/+ASM1/trace/+ASM1_rbal_9624.trc NOTE: cache initiating offline of disk 9 group 1 WARNING: initiating offline of disk 9.3915980183 (DISK18) with mask 0x7e NOTE: initiating PST update: grp = 1, dsk = 9, mode = 0x15 kfdp_updateDsk(): 17 kfdp_updateDskBg(): 17 ERROR: too many offline disks in PST (grp 1) I've tried KFED, only as far as comparing it's output between 2 disks. I'm now at a loss as to where to go next. Peter Nedeljkovich DBA Georgian College 705-728-1968 Ext. 1217