When installing the Outlook Add-in on a computer with Outlook 2007 installed, you may be prompted that .NET programmability support is not installed:
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This feature of Microsoft Outlook is installed by default if the Microsoft .NET Framework is installed when installing Microsoft Outlook, but not if you install the .NET Framework later.
To install .NET programmability support, launch the Microsoft Office or Microsoft Outlook installer (from Control Panel or the CD), choose to Add or Remove Features, and select the .NET programmability support feature under Microsoft Outlook:
This feature of Microsoft Outlook is installed by default if the Microsoft .NET Framework is installed when installing Microsoft Outlook, but not if you install the .NET Framework later.
To install .NET programmability support, launch the Microsoft Office or Microsoft Outlook installer (from Control Panel or the CD), choose to Add or Remove Features, and select the .NET programmability support feature under Microsoft Outlook: