ToolKit_RestoreReturnReceiptDays=<Number of days> sets the period of time within which a receipt confirmation request can be restored. After this period of time has expired, restoring is no longer possible. Possible values: 1 - 3600. Default: 7. With the default setting, the receipt confirmation can be restored until up to seven days after the email is moved to the quarantine. If set to 0, no restore period is checked at all. Also refer to: ToolKit_RestoreReturnReceipt.