property Message.SendOnce as Boolean
Indicates whether the message is sent once to the mail server, for all recipients, and the server takes the responsibility to delivery the message per all assigned recipients.

TypeDescription
Boolean A Boolean expression that specifies whether the message is sent once to the mail server, for all recipients, and the server takes the responsibility to delivery the message per all assigned recipients.
By default, the SendOnce property is False, which indicates that the message is sent individually to each recipients. The Send method sends the email message to the To, Cc and Bcc recipients.  Use the SendOnce property On True, to prevent overloading the mail server so the message is sent only once, and the server is responsible for delivering the message to recipients.