Preventing Out of Office Messages from being sent ou to distribution lists

Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ParametersSystem

Value: SuppressOOFsToDistributionLists (DWORD)

Set 1 to suppress or 0 to allow.

 

The setting should be set on mailbox servers.

 

The setting prevents sending OOFs unless the the recipient is in the TO,CC or BCC(if no one other recipients
appear in the other fields).