If you're setting up Outlook 2003 to work with Gmail for the first time, you'll need to:

Enable POP in Gmail

1.) Click the gear in the upper right then selecting Mail settings from the drop down.

2.) Select the Forwarding and POP/IMAP tab.

3.) Select Enable POP for all mail (even mail that's already been downloaded) or Enable POP for mail that arrives from now on



4.) Save Changes.

Use the following link to set up your Outlook:
Supported POP client list - Gmail Help


Enable IMAP in Gmail

1.) Same steps as above, but tick Enable IMAP



2.) Save changes.

Use the following link to set up your Outlook:
Supported IMAP client list - Gmail Help


Next:

Configure your Outlook 2003 client.

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