I have messages sent via iService, but the mailbox they used is unavailable. As a result, the messages are going to retry and fail to be delivered. How can I change the mailbox that it will use after it has been marked as sent?
Messages in the SMTPout table have a mailboxID that specifies the mail server to which they will be sent. You can run a SQL script to update this as follows.
update SmtpOut set mailboxID = NewMailboxID, timeSent = NULL where isSent = 0 and mailboxID = OldMailboxID
update SmtpOut set mailboxID = 22, timeSent = NULL where isSent = 0 and mailboxID = 1
In the example above, all messages that are not yet sent (isSent=0) that have a mailboxID of 1 will be changed to use mailboxID 22 instead.