When you send a message, your computer or mobile device is obviously not “sending” it, any more than a Star Trek transporter is “transporting” people to the surface of a planet. In both cases, the information that makes up the original is sent, but the original remains in place and is optionally deleted. (Yes, the crew is copied then destroyed, otherwise, you’d end up with a lot of Captain Kirks wandering around.)
With Mail for iOS and macOS, sent mail is always retained in a Sent mailbox. However, you can opt where that Sent folder is kept.
In macOS, find the settings through these steps:
Select Mail > Preferences and click Accounts.
Choose a mail account in the list at left and click the Mailbox Behaviors button.
The Sent Mailbox popup menu lets you select among various mailboxes, but note that you can store it in a mailbox associated with the account (at top) or in a local Sent folder under the On My Mac label.
In iOS, you have to drill down a bit farther:
Open Settings > Passwords & Accounts and tap the email account. (It can’t be the iCloud account, as it won’t let you choose email storage locations in iOS.)
Tap Account > Advanced > Sent Mailbox. (Not all mail hosts let you select this in iOS, such as Gmail, even if it appears as an option in Mail for macOS!)
In this list, you can again pick from choices on the server or under On My iPhone, the Sent mailbox.
If you pick the local mailbox (On My Mac, On My iPhone, or On My iPad), you might think your sent email wasn’t retained if you search from any of your other devices or use a web email interface to check mail. You can only find sent messages stored to a single device on that device, naturally; to keep a record of a message accessible from every device and via a web app you have to leave it on the server.
Some email hosting services separately let you control the behavior of whether sent email is retained when you use a web app. That can result in a problem where sent messages are moved to a Sent mailbox and then deleted by the mail host, either immediately or after a set number of days. For services other than iCloud and Gmail, check the settings at the mail host directly to ensure you won’t find those messages missing in the future.
As one more piece of belt-and-suspenders backups of my messages, I have a folder on my Mac to which I copy (but do not move) Sent email from my various accounts. This gives me a local backup in case there’s a server problem or I accidentally delete sent email from the server.
Now about those crew duplicates: “Scotty, don’t beam me down!”
This Mac 911 article is in response to a question submitted by Macworld reader Gloria.
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