If while running the configuration wizard you receive errors indicating that the configuration of the Enterprise Vault Monitoring database has failed, complete the configuration wizard and then run the Monitoring Configuration utility to configure the Monitoring database and the Monitoring agents manually.
For information on how to do this, see the following technical note on the Enterprise Vault Support Web site:
http://entsupport.symantec.com/docs/287449
The technical note also describes how to troubleshoot issues with Monitoring agents.