All email processed by Kerio MailServer is stored in the mail queue. Physically, this is the folder store/queue
in the directory where Kerio MailServer is installed. All messages are added to this queue as two files:
The file with the .eml
extension is the message itself
The file with the .env
extension is the message's SMTP envelope. This is used only for communication between SMTP servers and is discarded when the message is saved to the target mailbox.
Both files have identical names.
A message is sent from the mail queue either after it reaches the queue or in a time period defined in the scheduler — see chapter 11 Internet Connection for details. If the SMTP server sends messages straight to the target domains (i.e. no relay SMTP server is used) a situation can arise in which the message cannot be sent (no server for the target domain is available). In this case the message returns to the queue and is sent again later.
Note: If the server is in Offline mode, the message returns to the queue and the server attempts to send it again in a time specified in the scheduler (Next Try is only set in Online mode). If the server is in Offline mode (usually dial-up lines) then it is better to send messages via a relay SMTP server.
You may wish to check the mail queue if you suspect that messages are not leaving the server. Viewing the queue directly on the disk is not very easy, and is actually impossible if you administer Kerio MailServer remotely. For this reason it is possible to view the mail queue directly in the Kerio Administration Console in the Status → Message Queue section.
In addition to message queue, the tab includes also statistical data regarding current number of messages in the queue and their total size.
Each line of this window contains information about one message in the queue. The columns contain the following information:
Unique message identifier. This identifier also represents the file names under which the message is saved in the mail/queue
folder.
Date and time when the message entered the queue.
Date and time of the next attempt to send the message (you can set the attempts interval and the number of attempts in the Configuration → SMTP Server section — see chapter 12.2 SMTP server). ASAP stands for As Soon As Possible. This way sending messages that are queued for the first time — in the Online mode they are sent immediately, in the Offline they are queued and they are sent in scheduled time.
The size of the message (excluding the envelope).
The sender's and recipient's email addresses If the From field is empty, it is a DSN message sent by Kerio MailServer.
Status of the message (reason why the message has not been sent) is described in this column.
You can take the following actions using the buttons under the Mail Queue window:
The Mail Queue window is refreshed whenever a change occurs in the queue. You can also use the button to do this manually.
Removes the selected message from the queue. Click this button to display a menu to select messages to be deleted from the queue. You can delete only selected messages, all messages or messages that meet specific criteria.
Attempts to send the selected message immediately.
Starts sending messages from the queue.