ASKER
Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.
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Check the services are still running under the same Service account (BESAdmin or whatever you used).
Also check the BES MAGT logs and post more detailed errors.
Regards,
RobMobility.