At '%8' database copy '%1' on this server timed out on one or more Hung IOs. To help identify the specific failure, consult ...

At '%8' database copy '%1' on this server timed out on one or more Hung IOs. To help identify the specific failure, consult the Event log on the server for other storage and "ExchangeStoreDb" events. Service recovery was attempted by failover to another copy. Failover was unsuccessful in restoring the service. Error: %7