Adaptec 2810SA Device Failure

I hope someone can help. Got 1T on the line and although it is not
irreplaceable, would hate to have to reload.

I have a raid 5 that has 5 "optimal" drives and all appear to be
working (no symbols on the drive). But the Logical device has a big
red dot with a black x that says "failed". The only help i see on
Adpatec Storage Manager is to basically wipe it out and start over.
Would love to avoid that. The Managed Systems, raid (Local system)
and Controller 1 all have the yellow triangle with an exclamation
point.

What might have made this device fail and is it recoverable with all
the data?

Thanks in advance.