Users receive a - One or more of your reminders could not be snoozed or dismissed - error when they dismiss or snooze calendar reminders, how can I fix this?

The "One or more of your reminders could not be snoozed or dismissed" error can occur when the value of the user object attribute legacyExchangeDN is incorrect. To correct this error, follow Microsoft KB 556074 to correct the legacyExchangeDN attribute value for affected users. The Global Address Book should be rebuilt after updating the attribute.

NOTE: The Outlook AutoComplete function may continue to use the incorrect legacyExchangeDN value; add the "incorrect" value to the affected user's proxyAddresses attribute to ensure email delivery.