Autodiscover service, which allows Outlook 2007 and Windows Mobile 6.1 ActiveSync clients to obtain mailbox connection settings with little user intervention, isn’t configured by default in EBS 2008. In order to open Autodiscover service to both internal and external clients, you must follow several steps on both Messaging and Security servers: 1. Configure correct DNS records that’ll point external clients to proper URL for autodiscover service. 2. Install trusted SSL certificate on Forefront TMG web listener or distribute default EBS certificate. 3. Create Web Publishing rule in Forefront TMG to allow autodiscover requests from your external clients to reach Messaging server. 4. Add proper internal and external URL parameters to Autodiscover virtual directory on Messaging server.
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