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They are web services that are used by a growing number of applications and which help in configuring your mobile devices and desktop clients. Autodiscover is used by mobile devices including iPhone, iPod, iPad and Android devices, while Autoconfig is used by Thunderbird. Autodiscover used to be supported in older versions of Outlook, but it's not supported anymore for IMAP account setup. These services allow you to configure an e-mail account by only entering your e-mail address and password, without having to worry about incoming servers, outgoing servers or ports. All communication is configured to be secured through SSL by default.
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