Differences between MAPI, POP and IMAP
MAPI is a proprietary Microsoft protocol that allows the Microsoft Outlook email client to fully utilize all of the features of an Exchange server including email, shared address books, calendars and public folders. When Outlook is configured as a MAPI client, also known as an Exchange client, email is stored in the cloud on mail server with a copy on your computer. Messages retained in the cloud are accesible via webmail from any internet connected computer.
With MAPI, you can move messages from the cloud into a local file on your computer called a .PST file, a process through which copies of messages are deleted from the cloud and stored on your computer. This can allow for valuable storage space and help you create backups of your business-critical emails.
POP is the most common Internet standard for receiving email. When a POP email client retrieves messages, the messages are downloaded from Comcast’s secure mail server in the cloud onto your computer. The messages are normally deleted from the cloud, although you can configure your email client to not delete downloaded messages for a short period — for example, a few days.
POP is best used when you are only using one computer or device to access your email. If you plan to also use webmail and/or receive email on a mobile device, POP may not be the best option for you. POP is only used for receiving email and is commonly used in combination with the SMTP email protocol to allow email clients to both send and receive messages.
POP is an e-mail only protocol. Items such as contacts, appointments or tasks cannot be managed or accessed using POP.
IMAP is another common Internet standard for retrieving email. When an IMAP email client retrieves messages, it downloads a copy of messages from the cloud to your computer but leaves a copy in the cloud as well. The email client periodically synchronizes your mailbox between the cloud and the email client. When a message is deleted from the mailbox on the email client, it will be deleted from the cloud the next time the two are synchronized.
By keeping a copy of each message on the server, IMAP facilitates access to your email from more than one computer or email client — for example, Outlook on an office computer and via webmail from a home computer. IMAP is only used for receiving email and is commonly used in combination with the SMTP email protocol to provide both send and receive capabilities to email clients.
IMAP is an email only protocol. Items such as contacts, appointments and tasks cannot be managed or accessed using IMAP.
SMTP is the most common internet standard for sending email. When using SMTP, email is sent from your email client through Comcast’s secure mail servers to the recipient. SMTP is only used for sending email and is commonly used in combination with either POP or IMAP to provide both send and receive capabilities to email clients.