1. Open Apple Mail.
2. Click ‘Mail,’ and select ‘Preferences…’
3. Open the ‘Accounts’ tab, and click the plus sign (+) along the bottom to add a new account.
4. Enter ‘pop.googlemail.com’ in the ‘Incoming Mail Server:’ field.
5. Enter your Gmail username (including ‘@googlemail.com’) in the ‘User Name:’ field.
6. Enter your Gmail password in the ‘Password:’ field.
7. Select ‘Add Server…’ from the pop-up labelled ‘Outgoing Mail Server,’ and enter ‘smtp.googlemail.com’ in the ‘Outgoing Mail Server:’ field.
8. Enter ’587′ in the ‘Server port:’ field.
9. Tick the box next to ‘Use Secure Sockets Layer (SSL).’
10. Select ‘Password’ next to ‘Authentication:’ and enter your Gmail username (including ‘@googlemail.com) and Gmail password.
11. Click ‘OK.’
12. Click ‘Advanced’ and tick the box next to ‘Use SSL.’ (The port changes to ’995.’)
* Did you click ‘Save Changes’ after enabling POP in Gmail? To ensure that Gmail can communicate with your mail client, be sure to click ‘Save Changes’ on the Gmail ‘Mail Settings’ page.

MacOSXHints has another step-by-step tutorial.

UPDATED: 28 December 2005gmail, Google, mail.app, apple mail, POP accessSimilar Posts:

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