6.2  Important Notes

Non-secure and secure versions of the same service act as two separate services. This means that there are two different ways of accessing the same server and the user (client) can choose which one to use. For security and privacy protection reasons we strongly recommend using a secure version of any communication means. However, this must be supported by client software.

IMAP and HTTP access the same IMAP account in the same way. These two services can both be used (one at a time) without any limitations or risk. POP3 and IMAP/HTTP access the same physical account but POP3 can only retrieve messages stored in the INBOX folder, as it cannot “see” other folders. All incoming messages are stored in the INBOX folder. POP3 also downloads all messages from the server to the client machine. This can lead to the following complications:

  1. If a user logs into the account using POP3 first, all messages from the INBOX folder will be downloaded to his/her machine. After logging in using IMAP, these messages will no longer be at the server.

  2. If a user logs into the account using IMAP first (or uses HTTP) and moves messages to a folder other than INBOX, these messages will not be downloaded later using POP3.

  3. If a user has set rules such that all messages are moved to different folders, no messages will be accessible via POP3.