As Omar Shahine has pointed out in his blog, the current version of Inbox Manager (v1.0.2b) does not fully support access of Exchange mailboxes on two different machines. We're working on a solution and want to give you a heads up on our thinking.
Our proposed approach to implement this functionality is to create a ClearContext "slave" mode for users running Outlook 2003 Cached Exchange Mode dual configurations. When messages come in, they will only be processed by the "master" instance. When Cached Outlook is synced up with the network, the "slave" machine will receive the correctly scored messages. All Inbox Manager functionality (priority, topic assignment, filing etc.) will be available on the slave machine, with the exception that CC functions will not be available for use on new, unscored messages until they are scored and synced with the master.
We expect this to work well for users who have a primary Cached Outlook desktop running all the time plus a laptop. It doesn't work as well for people who might be running two machines as interchangeable primary workstations that are both connected/disconnected from the network frequently. The same approach can be used for other offline versions of Exchange, but the user must set Outlook on both machines to synchronize frequently.
We also have plans for an Exchange Server based version of our product. This is at least a couple of releases away - we will provide more details in future forum posts.
We plan to implement "Slave Mode" in an upcoming release - we will post a projected product roadmap when we finalize that information. As a workaround until we implement, users may disable ClearContext but retain the views on one of their machines to simulate slave/master functionality. That will, however, disable manual ClearContext functionality such as topic assignment and message priority adjustment.