How do I make Outlook Work Online / Offline?
If Outlook loses its connection to the Exchange server for a while, it may go into Offline mode. As long as Outlook is set to work offline, you will not be able to send and receive messages in the background – you will have to hit the Send/Receive button.
To see whether Outlook is working online or offline, look in the lower right corner of the screen. If you are connected to Exchange, it will look like one of these two pictures:
If you are working offline, it will look like this:
To remedy the problem, click the arrow to the right of "Offline" and uncheck the Work Offline option:
If you are still unable to connect to the Exchange server after unchecking Work Offline, it may look like this:
If this is the case then your computer may be disconnected from the network or the server isn't reachable. In this situation reboot and if it still shows disconnected and not one of the other options above then contact the IT department.