When trying to use the Out of Office Assistant from the tools menu in outlook 2003 you receive a message stating : –
The command is not available. See the program documentation about how to use this extension.
To resolve this problem you will need to re-enable the outex.dll addin/file.
To do this go to > Help > About Microsoft office outlook > Disabled items. Click on outex.dll and select enable.
Restart outlook and you should be good to go again!