I just had a case where what appears to be a perfectly normal disk suddenly went "dark". WHS thinks the drive is "missing" but there is no light at all on the MediaServer for that disk (slot 3). I think it should have turned red. Oddly, a little later another disk (slot 4) went "dark" but seemed to go un-noticed by WHS which said the drive was still "Healthy".
I couldn't get slot 3 to recognize the disk so I told WHS to removed and assume it was lost. Slot 3 still dead with this drive even those it works fine in another PC. So I told WHS to remove the slot 4 disk and it went through the process of moving the files to other drives.
Once both disks were out of the MediaServer then everything seemed ok. I could plug both disks back into the MediaServer and the disk lights went red as expected and I could add them back into the pool.
What gives? Did I get experience a nasty bug with the HP disk light driver or a hardware problem?