Siebel Email Response Administration Guide > Tables and Reference > How the Internet SMTP/POP3 Driver Processes Email Messages >

An Overview of the Processing Flow of Inbound Email Messages

When the Internet SMTP/POP3 Server driver starts, it creates required directories such as Incoming Email. The Internet SMTP/POP3 Server driver also creates a thread that polls the POP3 server. The PollingInterval driver parameter controls the frequency at which the Internet SMTP/POP3 Server driver checks the POP3 server for messages.

If there are messages, the Internet SMTP/POP3 Server driver retrieves and processes them one at a time, up to a maximum per session equal to the value set in the POP3 Batch Size driver parameter. If the current session with the POP3 server terminates abnormally, all messages previously retrieved, processed, and deleted during the current session will be restored, retrieved, and processed again the next time the Internet SMTP/POP3 Server driver connects to the POP3 server. The smaller the value POP3 Batch Size driver parameter, the fewer duplicate messages will be created and processed if a restart occurs.

Messages in a session are processed as shown in the following steps:

1. The POP3 RETR command downloads and saves a message to the Incoming Email directory. The message file name has name POP3_A_B_C_D_E_F.tmp.

   NOTE:  For more information about the files created by the Processing Flow, see Attachments Created by the POP3 SMTP Driver When Inbound Email is Received.

2. The POP3 DELE command deletes the message from the POP3 server.

   If the DELE command fails, the message stored in the Incoming Email directory is erased because it will be retrieved again in the next POP3 session.

   NOTE:  You should not have other email clients accessing the mailboxes that Siebel Email Response is monitoring because the email driver deletes the messages from the POP3 server when they are processed by Siebel Email Response. As such, these messages will not be visible from another client.

3. The disk based message is parsed. The parsing produces the following files in the Incoming Email directory:
   1. OriginalMessageText_A_B_C_D_E_F.txt.
   2. Any attachments parsed from message are given unique names as follows, ATT_A_B_C_D_E_F_G.DAT.
   3. Any remaining text or HTML fragments are turned into attachments and are given unique names, as follows ATT_A_B_C_D_E_F_G.DAT.
4. If an error occurs when the message is parsed, the following events occur:
   1. The temporary file POP3_A_B_C_D_E_F.tmp is moved to the Failed Email directory and any attachments created are deleted.
   2. The POP3 session is immediately terminated with a QUIT command so that the offending message is permanently deleted from the server.
5. If the Loopback Detection Interval parameter value is greater than zero and the message sender is currently being blocked, the following events occur:
   • If the Process If Loopback Detected parameter value is FALSE, the message is moved to the Loopback Email directory.
   • If the Process If Loopback Detected parameter value is TRUE, the driver's Loopback Candidate flag is set to TRUE and the message continues processing.
6. If the message is not moved to the Loopback Email directory or flagged as a loopback candidate, the POP3__A_B_C_D_E_F.tmp file is processed as follows:
   • If the Delete Processed Messages parameter value is TRUE, the temporary file is deleted.
   • If the Delete Processed Messages parameter value is FALSE, the temporary file is moved to the Processed Email directory.
7. The primary message text, header information (subject, to, cc, date, and so on), Loopback Candidate flag, and references to the attachments are passed to the driver's creator (usually Communications Inbound Receiver and Communications Inbound Processor).
8. The OriginalMessageText file and all the attachments are not deleted by the SMTP/POP3 driver. It is the responsibility of the workflow invoked by CIM to delete all the attachments.

   CAUTION:  Any errors that occur in the workflows may strand the ATT_A_B_C_D_E_F_G.DAT files in the Incoming Email folder. If this occurs while CIM is not running, the workflow invoked by CIM failed to process a message event. The safe way to determine if an ATT_A_B_C_D_E_F_G.DAT file can be deleted is to stop CIM and then look at the contents of all the queued CIM Events in all response groups to make sure that the ATT_A_B_C_D_E_F_G.DAT files are no longer being referenced.

NOTE:  For more information about the files created by the Processing Flow, see Attachments Created by the POP3 SMTP Driver When Inbound Email is Received.