When it comes to protocols to use with regards to email handling, there are a number available out there. Two of these protocols are SMTP and MAPI. The main difference between SMTP and MAPI is with what aspect of emails you can use them with. MAPI can be used for both sending and receiving emails as it has access to folders like the inbox and outbox. In contrast, SMTP is used exclusively for sending emails. In order to receive emails, you also need to use another protocol like POP or IMAP.
MAPI started out as a Microsoft protocol for use with their Outlook software. As Outlook gained popularity along with Microsoft’s Exchange server, more and more email clients also adapted the protocol. Still, MAPI does not enjoy the same widespread support that SMTP enjoys. Being around virtually since the invention of emails, all clients support the use of SMTP and is the default protocol in most cases. SMTP is also totally independent when it comes to the client, you can change clients without affecting functionality. With MAPI, you need to change some settings if you change clients as the server would not know that the client has been changed.
One advantageous feature of MAPI is its ability to automatically save a copy of send emails as it routes all emails through the outbox of the user. With SMTP, you do not get this feature built-in. But, you can still get the same functionality by including yourself in the BCC or if the server has been programmed to save a copy of the sent email into the sent folder.
For most people, there is really no choice between MAPI and SMTP as it is often dictated by company and what system they use in their email servers. For those who use Outlook and Microsoft Exchange server, it is logical to use MAPI as it was developed as a bridge between those two. For other people who use other email clients (i.e. Thunderbird) to connect to many of the free email servers (like Google’s Gmail), SMTP stands as a good protocol to use.
1.SMTP is only used for sending emails while MAPI is used for both sending and receiving
2.SMTP enjoys more widespread support than MAPI
3.SMTP is totally independent of the client but not MAPI
4.MAPI automatically saves a copy of sent emails while SMTP doesn’t