Reply Above This Line allows users to reply to a Case Discussion directly from their email mailbox using the Reply button, as you would with any other email reply. This functionality requires additional ClientSpace configuration for Email Integration. While the email templates (CSCDISC and CSCDISCNEW) themselves do not require Email Integration, the reply above the line functionality does. For Reply Above This Line to work, both CSCDISC and CSCDISCNEW must have a From Email Override address that matches an Active Email Integration mailbox. See Configuring Case Discussion: Reply Above This Line.