I have a client who wants to be able to open and view employees mailboxes. In Exchange 2003 I simply gave him permissions and he could access the mailbox via OWA. When we migrated to Exchange 2010 on a 2011 SBS over a year ago I gave him Full Managed Access and he could again access the mailboxes at first through OWA and then with Outlook 2010 they showed up automatically.
Recently he received a new PC with the latest version of Outlook 2010 and it added these managed mailboxes to his local OST file making it huge. I unchecked caching shared mailboxes and still the OST includes all mailboxes. Not using Cache makes Outlook crawl because it is trying to be real-time to all the mailboxes.
How can I give him access to be able to open every mailbox without it creating a large OST? I need quick access to his Mailbox and occasional access to the others. Accessing them through Outlook 2010 or OWA is acceptable.