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The problem of the peculiar cycle of failure.
Exchange 2010 no longer generate an automatic response (AutoReplay Outlook Out of Office). In Outlook 2010 does not also appear in the mail tips for absence.
There was no problem with setting OOF via Outlook and OWA.
Proved to be helpful to restart the Exchange Mailbox Assistants Services on the server.
The problem is basically trivial, but maybe someone will save time. The more that in Google for similar problems przypadu meets reconfiguration proposals and EWSa Autodiscover.
So before we start all over again to configure all the paths WebServices supported by the Exchange, we first try to restart the Exchange Mailbox Assistants service, perhaps so that we save a lot of time.
The solution can also be an additional dismount the database and mount it again.
In the case of DAG environment, just for a moment change the active database to another located on another server.
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Thank you very much. I had this issue (unable to send Out of Office) and I couldn’t find any solution in Internet. I realized that the Exchange Mailbox Assistants service was not started, even it was in Manual mode. Your post has confirmed me that this was the cause. Now it is running OK.