When setting up a new account, IMAP Push (if supported by the server) is enabled for the default incoming message folder, but is disabled for the account, giving you more control.
To enable IMAP Push, all you need to do is turn on “Enable IMAP Push” for the account. To open: long press the account in the main window (account list) and choose “Options and Folders”, then “Account options”.
To enable or disable IMAP Push for a specific folder, bring up “Options and folders” again, then “Folders”, scroll down to a particular folder, and tap the settings icon to the right of the folder’s name.
In addition, there are application-level settings to enable or disable IMAP Push, and/or restrict it to WiFi (e.g. use IMAP Push over WiFi when at home or at work, but don’t waste mobile traffic and battery juice while en route).
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When push is enabled, there should be a blue "@" notification icon in the status bar, saying "push mail: <account name> / <number of folders>". Are you seeing it?
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