Office365 Mailbox Access

Hi Experts

Question :  Does on-premises exchange 2010  user can add/access office 365 exchange user mailbox in his outlook 2010? If yes please would you explain how ?  or what step needs to do ?
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You can add full mailbox access for the mailbox via EMC, this happens when you have DIRSYNC working and enabled (so it can sync permissions to 365 and you don't have to do it via the portal) and your on-premises Exchange server has a connector to the office365 online services, once you give a user full mailbox access the mailbox should appear in mailbox\folder tree in outlook (you will have to restart outlook).

see here for full access permissions:

see here for DIRSYNC:

you must have both in order for this to work, you can install Dirsync on any active directory server.

Does it help?

If you have a hybrid setup then you can.
If you dont have hybrid then if you have a different SMTP domain. One for on-premises one for Office 365.
Vasil Michev (MVP)Commented:
Cross-premises permissions are not supported. It will work in some cases, but dont rely on it. Either move both the owner and delegate mailbox to the same place/org or ask them to share the credentials so they can configure the mailbox directly in Outlook.

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obaidoaAuthor Commented:
Hi Vasil

you are quit right ,cross-premises permissions are not supported .

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