Choose the correct incoming email protocol when setting up an email account:
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.
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 (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.
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.
When changing between protocols you will need to keep the following steps in mind:
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.