POP3 deletes emails from the server: fix

Introduction

If your email disappears from Webmail or does not show up on other devices, there is a good chance the mailbox is configured as POP3.

POP3 is an older way to check email. Its usual behavior is to download messages from the server to the device where the account is being checked. Depending on the program settings, it may then delete those messages from the server.

That is why a very common situation happens: messages appear on one computer, but disappear from Webmail, from the phone or from other devices.

What POP3 is and how it works

POP3 stands for Post Office Protocol version 3. It is a mail protocol that downloads messages from the server to a local device, such as a computer running Outlook or Thunderbird.

In a typical POP3 setup:

1. the mail program connects to the server
2. it downloads new messages
3. it stores them on the device
4. depending on the settings, it may remove them from the server

If you check the same mailbox from several devices, this can create confusion and make older mail appear to vanish.

Real example of what happens

Imagine this sequence:

1. You configure the mailbox in Outlook using POP3.
2. Outlook downloads the messages to the computer.
3. The setup does not leave a copy on the server.
4. Later, you open Webmail or check the mailbox from your phone.
5. The messages are no longer on the server.

The messages may still exist on the computer that downloaded them. But if that device fails, is reformatted or has no backup, those emails can be lost.

How to prevent POP3 from deleting email from the server

You have two main options:

• keep using POP3, but enable the option to leave a copy on the server
• switch the account to IMAP, which is usually the better long-term choice

Option 1: leave a copy on the server with POP3

If you want to keep using POP3, open your mail program settings and enable the option to keep a copy of the messages on the server.

In Outlook

1. Open Outlook.
2. Go to File.
3. Open Account Settings.
4. Select the affected account.
5. Click Change.
6. Choose More Settings.
7. Open the Advanced tab.
8. Check Leave a copy of messages on the server.
9. If you want, set how many days the server copy should stay there.

In Thunderbird

1. Open Thunderbird.
2. Go to Tools.
3. Open Account Settings.
4. Select the affected account.
5. Open Server Settings.
6. Check Leave messages on server.
7. If needed, define automatic deletion after a certain time.

Option 2: switch from POP3 to IMAP

If you check email from a phone, computer, tablet and Webmail, IMAP is usually the recommended setup.

With IMAP:

• messages stay on the server
• folders stay synchronized across devices
• read, moved or deleted mail is reflected everywhere
• the same mailbox is easier to manage from multiple places

Before moving from POP3 to IMAP, review whether you have messages stored only on one computer. If you do, create a backup before making the change.

Useful tips

1. Review every device

   A single device using POP3 without leaving a server copy is enough to make messages disappear from Webmail.

2. Use Webmail to confirm whether the message is still on the server

   If a message appears in Outlook but not in Webmail, it is probably stored only on that computer.

3. Make backups if you keep using POP3

   Especially when the messages are stored only on your computer.

4. If several people use the same mailbox, IMAP is safer

   For shared mailboxes, IMAP is usually the most practical option.

Frequently asked questions

Does POP3 always delete messages from the server

Not always. It depends on the program settings. In many POP3 configurations, messages are removed unless you enable the option to leave a copy on the server.

If I enable leave a copy on the server, does it restore already deleted messages

Not necessarily. That setting prevents future messages from being removed, but it does not automatically recover messages that were already deleted from the server.

Is IMAP better than POP3

For most people who check email from several devices, yes. IMAP keeps messages on the server and synchronizes changes.

Can I use POP3 on one device and IMAP on another

Technically yes, but it is not the safest setup. One badly configured POP3 device can still remove messages from the server.

Conclusion

If your messages disappear from the server, review whether any application is using POP3. You can prevent the issue by enabling the option to leave a copy on the server or, even better, by switching the mailbox to IMAP when you work from several devices.

If you need help reviewing the configuration, contact support and mention whether you use Outlook, Thunderbird, mobile mail, Webmail or another client.