Accessing Exchange from OS X - what restrictions are respected?
Outlook cannot enforce computer locking, that would require your Mac to be joined to the (Active Directory) domain and only AD logins permitted. There may be Outlook specific settings that are specified but there is no way to enforce computer locking (on a Mac) just by setting up an Exchange account in Outlook. Setting it up in Mail.app, well there is very little that can be done other than forcing a password change.