@omeganub
According to this link the answer is cant be restored
Yes, the majority of them do expire. When a mail expires, it is removed from your mailbox along with any unclaimed attachments (including Credits).
- You may notice that some of the timestamps on messages in your in-game mailbox are color coded:
- An amber timestamp means the message will expire soon.
- A red timestamp means the message will expire very soon.
- Mails sent to you by another player expire after 30 days if they are not opened, at which point they are returned to the original sender complete with any credits or items that may have been attached.
- If they are opened, they will still expire after 30 days but will not be returned to the original sender.
- Cash on delivery (COD) mails expire after 3 days, at which point the mail and any attached items are sent back to the original sender.
- Mails from the Galactic Trade Network (GTN) expire after 30 days.
- Mails from other players or game characters (for example, your Companion or a mission giver) expire after 30 days.
- If you transfer your character to another server, any mail that is in your mailbox will be deleted as part of the character transfer process.
- System generated mails for account based rewards do not expire, but will be deleted if you transfer your character.
NOTE: Our Customer Service team cannot restore expired or deleted mails, or any of their attachments.
