Polling for new messages
If you are using a desktop client, do not set it to automatically check for new messages more frequently than every 10 minutes. Doing so puts an uncessary load on the e-mail servers.
Did you know just one user setting their client to check every minute could genetate 720 logins per day, 5,040 logins per week, and 262,080 logins per year! Imagine the impact of 10 users doing this, or 100, or 1000! Remember that we have over 7500 users on this system!
If you need to check for new messages more frequently, leave automatic polling off altogether and use the manual method.