The VMFS volume is corrupt.
I/O error, perhaps caused by bad shutdown due to power failure, or faulty controller/connection.
It is probable that the data is not recoverable. Stop using the corrupted datastore.
It is strongly advised to contact VMware Support if you need to recover any data from the corrupted volume.
Refer to this VMware KB article for more information.
Refer to the VMware Online Documentation for more information on vCenter event messages and possible solutions.