Additional Outlook 2010 mailbox - only Inbox folder displays

Outlook 2010

I have configured an email client to have access (with owner priviliges) to another mailbox and it works perfectly - almost.

The only folder displayed is the Inbox and the user requires access to the Sent box as well. The Sent is showing as the user has access to the Sent but no go.

Any ideas anyone please?

Many thanks

 

I apologise yes, running on Server 2008.

 

I only want the user to be able to see the Sent folder, not send email.

What I've done is on "User A" I've given "User B" full permissions, and on "User B" I've added "User A" as an additional mailbox - and vice versa actually.

I've not made any changes on the Exchange server and these are the only users that require "cross permissions".

Many thanks...