You can download your Gmail messages to another computer at any time.* To download messages you received before enabling POP, just follow these steps:
- Sign in to Gmail.
- Click Settings at the top of any Gmail page.
- Click Forwarding and POP/IMAP.
- Select Enable POP for all mail.
- Choose the action you'd like your Gmail messages to take after they are accessed with POP.
- Click Save Changes.
- Configure your POP client.
* All messages may be downloaded to another computer once; after downloading mail, it will not download again.