POP vs IMAP – What’s the difference?

Overview of POP vs IMAP:

• Do you use more than one device for email (e.g. desktop & mobile)? Then IMAP is your best choice – but watch out for disk over–usage on your hosting account.
• Do you download email to only one device e.g. your computer? Then POP is an option.
• If in doubt use IMAP

Choose the correct incoming email protocol when setting up an email account:

POP 

Port 110

POP (Post Office Protocol) simply downloads email to your computer and then deletes the email from the server. If you access your email on more than one device (desktop, laptop, tablet or phone), your mailboxes will not synchronise. 

Best uses for POP Accounts:

• When disk usage on the server needs to be used sparingly.
• When emails can be backed up locally on the device(s) and server backups are not as important.
• When synchronization of folders from the device to the server and with other devices is not a requirement.

Pros:

1. If you want to send and receive your emails through one device, a POP account is suitable.
2. As emails are downloaded and usually removed from the server, you don’t risk disk over-usage charges on your hosting account.

Cons:

1. Data loss is possible if your computer is stolen or corrupted, as the mail is removed from the server.
2. Synchronisation of sent emails is not possible. All emails in the sent folder need to be backed up locally.

If you don’t use IMAP but would like to store copies of incoming mails on the server, then set up your mail client to leave a copy of messages on the server.

IMAP 

Port 143

IMAP (Internet Message Access Protocol) is the most modern and widely used protocol, which can download AND upload (synchronise) data with the server whereas the POP protocol is a download–only protocol and thus will not be able to upload data to a server. IMAP can synchronise advanced permissions and other folders and is also able to distinguish between already read/opened mail from device to device.

 Best uses for IMAP Accounts:

• When you want to synchronise / mirror image your account emails and folders with the server and with other devices.
• When the increased disk usage that this configuration will consume on the hosting server is not as much of a concern.
• When reliance on the server backup system is more convenient than backing up the email account locally. (Kindly remember that the Backup System is not guaranteed).

Pros:

1. All email and folders are synchronised and stored on the server.
2. Folder and file directories will appear the same way each time you setup the same account on a different device.
3. You can switch between your email software and the webmail interface at any time and the same emails should still reflect.
4. If the data stored on your computer is corrupted, formatted or if your computer is stolen your emails will still be available on the server.

Cons:

1. Your disk usage on the server builds up quickly depending on the volume of emails received/sent.
2. You will need to continuously remove unwanted emails to control server disk usage.

IMAP–Root Folder Path / Root Document Path

The IMAP Path Prefix is a setting entered into your email software settings that tells the software that it should synchronise ALL of the folders currently active on the server with the device. It is a commonly used setting that when specified, ensures that all folders are effectively synchronised.

The IMAP path prefix is INBOX. Please be sure to enter this in all caps.

This setting can be entered by clicking on “File > Account Settings > More Settings > Advanced” within most versions of Microsoft Outlook. Android devices can specify the IMAP path prefix within the “Incoming Server” settings menu.

The IMAP path prefix is generally pre–configured in most email software packages and on most devices but can be useful when troubleshooting folder synchronisation difficulties.

Changing protocols

When changing between protocols you will need to keep the following steps in mind:

1. Make a local backup of the emails currently on the device– ensuring that if the current protocol is IMAP that the emails being backed up include the full email body content as well as the attachment.
2. Remove the current account.
3. Recreate the new account selecting the new protocol.
4. Import or “drag and drop” the locally backed up emails and folders into the newly created account.
5. If the newly selected protocol is the IMAP protocol, you will need to allow some time for the newly imported emails to re–synchronised (upload) to the server.

Missing Emails

If you have a POP device configured with the ‘Leave a copy of messages on the server’ option unchecked, emails will automatically be removed from the server after downloading them to your device or software. As such, if you have additional POP or IMAP devices that are configured to send and receive emails to/from the same email account, when these devices connect to the server, the emails downloaded by the POP device will no longer be available to download from the server.

The same can be said for POP accounts that are configured to remove copies from the server after (X / 10 / 14) amount of days. If there is another device that synchronises with the server via the IMAP protocol, when the emails are removed from the server after (X / 10 / 14) amount of days, the IMAP device will reflect this change which will result in the emails “going missing”. In this case, the emails will need to be sourced locally on the device connecting via the POP protocol.