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Whether you should use POP or IMAP is very much a matter of personal preference. POP is a one way download - it accesses Gmail's All Mail and downloads everything (except Spam and Trash) into the client's Inbox. Once that has happened then no actions you perform on your mail will show up in Gmail, and vice versa. So it's good for backups or if you are concerned about keeping permanent records. IMAP is a full two-way sync, where the client will always mirror what's in your Gmail account. So if you delete mail in the client, that will sync back to Gmail, and if you perform actions in Gmail, they will sync back to the client. The settings you need for Outlook are: Incoming Mail (IMAP) Server - Requires SSL imap.gmail.com Port: 993 Requires SSL:Yes Incoming Mail (POP3) Server - requires SSL: pop.gmail.com Use SSL: Yes Port: 995 Outgoing Mail (SMTP) Server - Requires TLS or SSL smtp.gmail.com Port: 465 or 587 Requires SSL: Yes Requires authentication: Yes Use sam...