You can set the following registry entry to control what the Exchange Journaling task does if a distribution list is invalid.
To manage invalid distribution lists
Log on to the Journaling task computer as the Vault Service account.
Run regedit and navigate to the following location:
HKEY_LOCAL_MACHINE \Software \KVS \Enterprise Vault \Agents
Create a new DWORD value with the name ActionForInvalidDL and set its value to one of the following: