How do I make my mail program leave a copy of my messages on the server?

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If you use the POP3 protocol to read mail sent to an email mailbox, many programs (such as Outlook) will delete the messages from our mail servers as soon as the program sees them. That means you can't later use Webmail or another mail program to view the same messages on our servers.

This may be what's happening if some messages are being deleted unexpectedly from your Inbox before you see them. For example, when you check your mail from several devices, you might notice that sometimes messages only appear on some of the devices. That happens when one of the POP3 connections deletes the message before the others have a chance to see it.

If you use multiple devices to read email, we recommend using an IMAP connection (not a POP3 connection) for all the devices. But if you do need to use POP3 on any of them, you should set your mail program to leave a copy of the messages on our servers for at least a few days after it sees them. Then you can view your messages another way if you delete them from your mail program by accident or have other mail program problems.

We have specific pages showing how to set various programs to leave messages on the server. Note that you don't need to follow these instructions if you use IMAP to read mail instead of POP3; IMAP always leaves messages on the server.

Is there a way to completely block POP3 deletions?

If you don’t want a POP3 program that you use to delete your mail, and you can’t easily adjust the settings of that program, we offer users a way to completely block POP3 deletions for an address (while still allowing IMAP and webmail deletions).

The easiest way to enable this is to contact us and ask us to turn this feature on.

If you’re a technically advanced user who is comfortable with the command-line shell, you can do it yourself by running the script named “pop3-deletions”, like this:

example.com:~$ pop3-deletions address@example.com

(This is exactly what we do if you ask us to enable it.) It will ask you to confirm that you want to enable POP3 deletion protection.

After doing this, any POP3 connection that tries to delete mail will see the error “-ERR POP3 deletions are not allowed”.