The similar error message can appear in the following situation (Exchange 2010 RTM + Firefox), which has been fixed in the exchange 2010 SP1. So,
please check the browser type on the problematic machine, and the exchange 2010 version
Please check if there’s any related error event in the application log on the CAS server
Please check if the issue can be reproduced on a newly created mailbox
Please increase the diagnostic logging level on the control panel component
Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.
Proposed as answer byAlan.GimThursday, December 16, 2010 6:14 AM
Marked as answer byAlan.GimFriday, December 17, 2010 11:08 AM
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