IMAP and POP3 are ways an email application accesses messages. SMTP handles outgoing mail. Microsoft Exchange is a messaging service with its own client connection options, rather than another name for IMAP. The right setup depends on your provider, applications and the information staff need to share.
IMAP: keep mailbox folders in sync
IMAP lets supported applications work with the folders and messages in a server mailbox. Read status, moves and deletions can synchronise between devices. It is generally the practical starting point for a mailbox used on both a phone and computer. See Microsoft's explanation of IMAP and POP.
Some applications keep downloaded copies for offline reading, depending on their settings. New mail and synchronisation still require a connection. An ordinary archive folder inside the IMAP mailbox normally remains on the server; moving mail there does not by itself reduce the server quota.
POP3: download mail with care
POP3 downloads incoming messages. Applications may remove downloaded mail from the server or retain copies, depending on configuration. It does not provide the same folder and read-state synchronisation as IMAP. Check both the application and provider settings before assuming messages remain available elsewhere.
If your only copy is on a computer, include it in a backup you can restore. Before changing accounts or replacing the computer, identify local folders and confirm that the required messages have been preserved.
SMTP: the outgoing side of email
An IMAP or POP mailbox can receive successfully while sending fails because its outgoing configuration is separate. Use the server name, encryption and authentication supplied for that mailbox. Microsoft lists SMTP separately from incoming settings in its email application guidance. Do not copy an unrelated provider's settings or disable certificate checks to make a connection work.
Where Microsoft Exchange fits
Exchange is a service that can support richer mailbox features through compatible clients. Microsoft documents Outlook using MAPI, browser access and Exchange ActiveSync, as well as separately configurable POP and IMAP access. POP or IMAP access does not itself provide Exchange's wider collaboration experience. See Microsoft's Exchange protocol documentation.
Ask which calendar, contact and shared-mailbox features your subscription and client actually support. The Outlook application can connect to several types of account, so its name alone does not identify your email service.
Synchronisation is different from a backup
If deletion synchronises across devices, another device may lose the message too. A local cache is not automatically a separate, recoverable archive. Establish what is backed up, where copies are kept and who can restore them before relying on a setup.
When storage is full, find out whether the quota applies to the mailbox or the overall hosting account. Preserve any required records before removing mail. Ask for help if it is unclear whether an archive is local or still held on the server.
Before changing your configuration
- Confirm the actual email provider and the supported account type.
- Obtain the correct incoming and outgoing settings directly from that provider.
- Identify local-only mail and make a recoverable copy.
- Check sent folders, contacts, calendars and any shared access that must remain available.
- Test the new setup before removing the old profile or service.
For a new business address, read our professional email guide. If you need to discuss mailbox numbers, storage and website hosting together, view the hosting options or contact SDDS.