Restore from backup.
IO problems, like most causes of corruption, or someone tried something stupid like replacing the data or log files with older ones, or maybe a HA/DR 'solution' like SAN snapshots that doesn't support SQL and hence is more a gamble than a solution
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability