How does in-game mail work?
In DC Universe Online, mail may be retrieved, composed, or sent at any mail terminal located in the Hall of Doom, the Justice Tower, Safe Houses, Police Stations, or any Lair Mail Amenity. These terminals will display a letter icon over them.
Once players have interacted with the terminal, they can choose to compose and send mail to other players as well as view mail sent to them in their inbox. Cash and tradable items may also be mailed to a player by choosing the "attach item" option. In order to view mail you have already sent, simply choose the "Sent" section at the top of the menu; the screen will display all previous mail sent on the left side box.
Mail received may only be held for 30 days, at which time it will be sent back to the sender. Any attachments that haven't been claimed in mail should be automatically placed into your character's inventory or overflow. The text of mail will also change color depending on the age of the mail; once the mail has become 30 days old, it is deleted and/or sent back:
White: Less than 25 days old
Yellow: Over 25 days old
Red: Over 28 days old
Depending on level of membership, mail may be held in the archive section so that it is never deleted. The age of each archived mail may be located in the right hand corner of the content screen.
These are the current archive limits for each membership: