Copy the data to a mailbox or pst folder, then export from there.
Or, qand dirty method:
1. Use a table view to display all the data fields that you want to export
to Excel.
2. Choose Edit | Select All.
3. Choose Edit | Copy.
4. Paste to Excel.
Note that you won't get information on individual appointment recurrences.
Otherwise, you'd have to write custom code or use a third-party application.
See http://www.slipstick.com/dev/customimport.htm.

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Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
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> We are using a calendar in a public folder to keep track of projects in our
> office.
[quoted text clipped - 3 lines]
>
> How can we export the data from a public folder?