What is Active Sync?

(Exchange) ActiveSync is a protocol that Microsoft Exchange Server uses to communicate with Windows Mobile clients and other devices that have licensed the ActiveSync protocol.

It provides access to the mobile device’s folder structure, contacts and appointments, synchronizing changes in Personal Information Manager made on the PC or PDA.

ActiveSync used to be a good way to be notified immediately of new incoming e-mail messages, as they are actively pushed to the mobile device and synchronized immediately.

Nowadays, ActiveSync is no longer absolutely necessary, as all smartphones and desktop mail software can continuously monitor IMAP accounts and any new messages appear in the recipient’s mailbox almost instantly. Therefore, ActiveSync is currently used in environments with Microsoft software only.

Mailix supports ActiveSync for mailboxes.

See also:
Wikipedia: Active Sync