Since a security patch in late 2013, a few users have reported that they are not getting notifications of new emails within Outlook (but can in OWA and Activesync). These users are using category views.. There is no fix from Microsoft at the time of writing but a workaround is to change Outlook to cached mode. This can easily be done on a SHU PC by using the [MD Help] application that is available from the Start Menu and selecting the Cached Exchange Mode option from the [Self Service Tasks]