My spool is full of pending messages. What do I do?

There are many reasons why a Web server’s spool can become backed up with messages pending delivery: a user sending an abnormally large number of messages or, most commonly, a compromised account being used to send spam. When this occurs, you may notice a slow-down in mail services, like not receiving customers’ messages as quickly as anticipated or a delay in messages sending from the server. The simplest way to quickly get messages flowing through the spool again, without potentially losing valid messages, is to create a new, empty spool folder and move around the message files.
(If you’re worried your spool is backed up as a result of a spammer, check out these KBs on how to Find a Compromised Account and suggestions on the Recommended Spam Settings.)
Follow these steps to clear out your backed up spool and get messages flowing again:
  1. From your server’s Services control panel, stop the SmarterMail service.
  2. Locate SmarterMail’s spool folder. By default, this is located at C:\SmarterMail\Spool.
  3. Rename the ‘Spool’ folder by right-clicking on the folder and choosing Rename. In this example, we’ll call the renamed spool folder “spool_old“.
  4. Restart the SmarterMail service from the Services control panel. SmarterMail will recreate a standard, empty spool folder called ‘Spool’ and begin using this for sending / receiving messages.
  5. Once you’ve figured out what was causing the back up of your spool, and have that issue resolved, you can slowly move valid messages (in their .EML and .HDR format) from ‘spool_old’ to the new ‘Spool’ folder created by SmarterMail.
Additional Information
  • If you’ve found that your backed up spool was the result of a spammer, you can search through the ‘old_spool’ folder to find invalid messages. Generally, all messages sent by the spammer will be the same file size. When found, you can delete them outright or move them to a third folder for later review.
  • Inundated by incoming spam? Get a free, 30 day trial of Message Sniffer or Cyren Premium Antispam -- both available as third-party add-ons that act as an additional spam checks.