SMTP transaction logging The SMTP transaction log is intended to be a forensic tool that tracks all SMTP commands sent and received by Internet Services, as well as the Subject and Message-ID, which allows you to verify what email has (or hasn't) been sent or received. This is a separate log file from the diagnostic log file and can be enabled with minimal impact on performance. All inbound and outbound SMTP transfers are logged in a file named smtp-YYYYMMDD.log. Log entries are in the form: [<date and time>] <Client or Server>-<TID>: <what>: <data> where             [<date and time>] is in the same format as the log file <Client or Server> is Client when IS is sending a message to another SMTP server or Server when IS is receiving a message <TID> is the task id as in the log file <what> is one of Snd, Rcv, ID or Sub Snd and Rcv are used the same as in the log file (the SMTP commands). ID indicates the Message-ID of the message. Sub is the Subject. <data> is what was sent, received, the Message-ID or the Subject. To configure and activate the SMTP transaction log, fill in the SMTP Log tab on the Advanced Mail form.