Open Messaging, and select Options > Settings > E-mail > Mailboxes.

Open a mailbox, and select Retrieval settings > Retrieval amount.

To specify the number of e-mail messages to retrieve automatically or when you connect to a remote mailbox, select from the following:

For the IMAP4 mailbox type, you can select different retrieval amounts for Inbox and other mailbox folders to which you have subscribed.

If you use automatic retrieval of new e-mail messages,All is the default value for this setting.

To save your settings, select Back.