Change How Often Postbox Checks For New Mail
Postbox will check your accounts for new messages periodically. Nonetheless, you can control the interval at which Postbox will check for new messages, and many IMAP accounts support the IDLE command, which notifies Postbox of incoming messages automatically. The sections below outline the ways Postbox can check for new messages:
Manually Check for Messages
If you're expecting an incoming message and don't want to wait for it to appear, you can tell Postbox to check for new messages for a specific account. First, select the account in the Accounts Pane, and click the "Get New Messages" button in the toolbar. Alternatively, clicking the small arrow next to this button will reveal the options to check for new messages in a different account, or all accounts at once.
Additionally, each time you click on an account or folder, Postbox will check for new messages in that location automatically.
Customize How Often Postbox Checks for Messages
Postbox will automatically check accounts for messages once every 10 minutes. To customize this interval for a specific account, or disable automatic checking completely, open the Account Settings at the following location:
Mac: Preferences > Accounts > [your account]
Windows: Tools > Options > Accounts > [your account]
In this window, find the option to "Check for new messages every ____ minutes", and decide on your preferred interval.
Note: Some POP servers place limits on how often a mail client can check for messages, so we don't recommend decreasing the interval under 10 minutes.
Checking IMAP Folders for New Messages Automatically
By default, Postbox will only check the Inbox for new messages at the chosen interval. However, it's possible to include certain IMAP folders to be checked for new messages as well. Please see this article to learn how.
IMAP and the IDLE Command
Users of IMAP accounts may notice that messages are downloaded in Postbox almost immediately. This is because many IMAP servers support the IDLE command, which maintains a connection with the server to update accounts automatically. IDLE is turned on in Postbox by default.