Learn to create a COM add-in that adds a custom tab, group, and other controls to the user interface.
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Video: Create Add-ins to Customize the Office 2010 Backstage View
Video: Create Add-ins to Customize the Office 2010 Backstage View
Sharing Custom Tabs in The Ribbon UI
To let add-ins (native, unmanaged/managed COM add-ins and VSTO add-ins) share tabs is a good strategy but it can be applied in two different ways. Which to apply is depended on the individual add-ins. Sharing the Add-ins Tab For small application it is not necessary to use tabs on their own
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Sharing Custom Tabs in The Ribbon UI