Use the Set-ReceiveConnector cmdlet to modify an existing Receive connector on a computer that has the Hub Transport server role or the Edge Transport server role installed.

set-ReceiveConnector “Default ” -permissiongroups:”ExchangeUsers,ExchangeServers,ExchangeLegacyServers,AnonymousUsers”
set-ReceiveConnector “Default ” -tarpitinterval 00:00:2