GMail Apps - Apple Mail 4.0 (Mail Client Setting - POP)

Please note that if you're adding your Gmail address to Apple Mail 4.0 for the first time with automatic configuration, your mail will be configured for IMAP1 access.
In order to configure POP2 Gmail account for the first time, please follow these steps carefully:

1. Enable POP. Don't forget to click Save Changes when you're done.
2. Open your Apple Mail client
3. Fill in the ‘Welcome to Mail’ window with the following information:
• Full Name: [your name]
• Email Address: your full email address [username@gmail.com, or username@your_domain.com for Google Apps users]
• Password: your Gmail password
• Important: Hold the option button down until ‘Create’ turns into ‘Continue’


4. Click Continue
5. Fill in the following Incoming Mail Server information:
• Account Type: Select POP
• Incoming Mail Server: Change this to pop.gmail.com
• User Name: your full email address [username@gmail.com, or username@your_domain.com for Google Apps users]
• Password: your Gmail password
• Important: Hold the option button down until ‘Create’ turns into ‘Continue’


6. Click Continue
7. Incoming Mail Security
• Use Secure Sockets Layer (SSL): selected
• Authentication: Password
• Important: Hold the option button down until ‘Create’ turns into ‘Continue’


8. Click Continue
9. Enter the following Outgoing Mail Server information:
• You can leave description blank - this field is optional
• Outgoing Mail Server: smtp.gmail.com
• Use Authentication: selected
• User Name: your full Gmail address [username@gmail.com, or username@your_domain.com for Google Apps users]
• Password: your Gmail password
• Important: Hold the option button down until ‘Create’ turns into ‘Continue’


10. Click Continue.
11. Outgoing Mail Security
• Use Secure Sockets Layer (SSL): selected
• Authentication: Password
• Important: Hold the option button down until ‘Create’ turns into ‘Continue’


12. Click Continue
13. Review your Account Summary and uncheck Take account online as you will need to adjust your incoming port number
14. Click Create


15. Once your client opens, you’ll need to change your incoming port number to 995. To edit your incoming port number, please click Mail>Preferences... > Accounts tab > Advanced
    • Important: Your port number must be 995
    
    
16. After you’ve updated your port number, you can take your accounts online and download new messages by clicking Mailbox > Get All New Mail

If you have already configured Apple Mail 4 for POP and are trying to add an additional email, please start by following these steps:

1. Click Mail > Preferences....
2. On the Accounts tab, click the + button to add a new account.
3. You will then need to repeat the steps above.

1. IMAP: IMAP (Internet message access protocol) lets you download messages from Gmail so you can access your mail with a program like Outlook Express or Apple Mail. IMAP syncs the actions you take in Outlook Express or Apple Mail with Gmail so if you read a message in your mail client, it'll be marked as read in Gmail.
2. POP: POP (Post office protocol) is a one-way download of your messages that allows you to access your mail with a mail program like Outlook Express or Apple Mail. POP only offers one-way communication, which means that actions you take in the mail program (like marking a message as read) won’t be synced to Gmail.

Source: [http://support.google.com/mail/bin/answer.py?hl=en&answer=181714]