"Out of office Assistant" in outlook gives error

When you select 'Out Of Office Assistant' from the Tools drop down menu of Outlook 2003, it gives an error message "'the command is not available. See the program documentation about how to use this extension".

To resolve the problem.

Click on help menu and then click on "About Microsoft Outlook".

Click on the Disabled Items entry. You will see a Disabled Items window open, with the following information within it:
The items below were disabled because they prevented Outlook from functioning correctly.
Please note that you may have to restart Outlook for these changes to take place.
Select the ones you wish to re-enable.
If you see "Addin: outex.dll (outex.dll)" listed, click on it to highlight it and then click on the Enable button. Then click on the Close button. Then click on the OK button to close the About Microsoft Office Outlook window.