Outlook 2007 Cached Exchange Mode

Configuring Cached Exchange Mode in Outlook turns on Outlook's ability to download a copy of your user's mailbox to the local drive. The biggest advantage of this is improved performance on slower or troublesome networks and the ability to work offline. I use it mainly for laptop users, who don't always have a stable connection. I don't recommend this for desktops on your LAN that are always online.

Open Outlook and goto Tools > Account Settings...

You will get this window. Click on Change...

Check mark Use Cached Exchange Mode

Click Next then Finish

You will be prompted to restart Outlook

Synchronization will occur once Outlook is able to establish a connection with the Exchange server. Depending on how much email you have received since your last synch and the speed of your connection, it could take a while to update if you have a slow connection and many new emails.

Once synchronized, you should have those emails offline.