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POP vs. IMAP

WiscMail offers multiple ways for your email client to get your mail. WiscMail still supports both IMAP and POP protocols.

What is the difference between IMAP and POP?

IMAP

IMAP (Internet Message Access Protocol) is a standard protocol for accessing e-mail from your local server. IMAP is a client/server protocol in which e-mail is received and held for you by your Internet server. You (or your e-mail client) can view just the heading and the sender of the letter and then decide whether to download the mail. You can also create and manipulate folders or mailboxes on the server, delete messages, or search for certain parts or an entire note. IMAP requires continual access to the server during the time that you are working with your mail.

POP

POP3 (Post Office Protocol 3) is a less sophisticated protocol than IMAP. With POP3, your mail is saved for you in your mailbox on the server. When you read your mail, all of it is immediately downloaded to your computer and no longer maintained on the server. WiscWorld used the POP3 protocol.

If you are interested in more details about these protocols, please visit the following sites:

What is SSL?

Secure Socket Layer (SSL) allows your client to communicate with the server with an encrypted certificate, ensuring the security of your password and your email. Both IMAP and POP support using the SSL encryption protocol to access your mail. The POP protocol using SSL is commonly called SPOP; the IMAP protocol using SSL is generally referred to as Secure IMAP.

What is the difference between using IMAP and leaving your mail on the server using POP?

The "leaving mail on the server" option in a POP system is a temporary central storage location when using multiple computers.  An example of an appropriate use of this feature would be setting your local POP client to leave mail on the server at work and setting your home PC to not leave mail on the server thus allowing you to view your mail at work, but always store your mail at home.  Leaving mail on the server in a POP system is not designed to be a permanent message storage location; many internet service providers offering POP mail (including WiscWorld) will only allow mail to remain the server for a limited time period.  

IMAP is designed to be a permanent message storage location. It also allows you to organize and store your messages in folders that also remain on the server. These messages and folder structure are designed to be viewed from any location you are set up to access them.

Which is better: IMAP or POP?

Although IMAP is a superior technology and we recommend using it, the POP protocol still works with WiscMail. Many people prefer POP's straight-forward approach to email, so you can decide which is better for you. You can set up your email clients to use the POP or the IMAP protocol, but not both. You may experience synchronization problems if you use an email client configured for IMAP on one computer and an email client configured for POP on a different computer. You should decide which protocol is best for you, and then use it on all of your email clients.

Where does the WiscMail web client fit in?

The web client works with both POP and IMAP. If you use POP, you will not be able to see any of the mail that you have already viewed on your local computer (unless you have it set to leave mail on the server). You will only be able to see the new mail on the server. If you wish to view your old mail, you will have to go to the computer that you downloaded the mail to and view it in your email client. If you use IMAP, you will be able to see all of your mail and all of your IMAP folders that you created.  The web client is essentially the same as an IMAP client program on your computer.