Have you just noticed that all of your appointments and calendar events have been deleted from Outlook prior to a current month? Are you using a Blackberry or other PDA device and this has not happened before? Your archive calendar is also empty.
Are you also missing addresses from your address book? You can try to search for any and all .pst files on your computer. Outlook .pst files are archive files.
Also, make sure that you don’t have “Delete expired items” checked in your Outlook configuration settings. You can also set Outlook to automatically auto archive your events. Basically, archived items are stored in a compressed archive .pst file.
You can’t read those entries on fly, but you can restore those archived events when needed. It’s also recommended to backup your archive .pst files if that information is important enough to you. You can check your “Deleted Items” folder in Outlook.
Also, please check your sync settings on your Blackberry. By default some handhelds will delete appointments after 60 days old or whatever their default setting is. I think this is what makes most sense right now. Even if you can’t recover your past appointments, please make sure you check out your Blackberry settings and change them to forever or enable Auto Archive in Outlook.
I’m afraid if they are not archived or in deleted items than it might not be possible. If you configure your Blackberry and or Outlook to save or archive your items, as well as backup your archive file, if you create one, then in future you will be able to restore your items. These tips were written for a computer running Microsoft Windows Vista, Outlook email client, and Blackberry Storm PDA but can certainly be used as a basis for other windows computers with Outlook installed and synced with other personal digital assistants.