Why does Outlook 2003 not seem to be sending or receiving automatically?

At Subvenion, we get asked this all the time, so we though we would create a page specifically to answer this question.

Outlook 2003 allows you to read and write email even when you are not connected to your Exchange Server by maintaining a 'cached' local copy of your data.

Outlook will switch to using this 'cached' data when it can't see its exchange server. The problem is that it doesn't always switch back out of this mode. So, for example, if your server reboots while your Outlook is running, or your wireless connection is interrupted, your Outlook may go into this mode. Your indication that it has done this is that in the bottom right corner of your Outlook window,the status will change from 'Connected' to 'Disconnected'. At this point, pressing Send/Receive will forcibly make a connection to the server if possible and send and receive new mail.

If this has happened to you, simply right click on the 'Disconnected' status and uncheck the 'Work Offline' option. Assuming it can connect to the server, Outlook should then go back into 'Connected' mode.

(This only applies to Outlook 2003 connecting to an Exchange 2003 server)