The CEO's assistant has permission to see his Inbox. However, the assistant needs to move items out of the Inbox into subordinate folders, but the folders don't appear in the assistant's Microsoft Outlook client when the assistant has the CEO's Inbox open. What's causing this behavior?
This Outlook behavior is by design. Microsoft (rightly, in my opinion) decided that giving other people permission to see your Inbox shouldn't automatically give them permission to see every other folder the Inbox contains. The CEO must explicitly give the assistant permission to view the folders he wants the assistant to access; granting delegate access only on the Inbox won't do the trick.