Office Tab is based on the standard Microsoft Office Add-in Technology. Base on the document, CustomTab will add a custom tab to the ribbon, I think we could not use the same custom tab even through you use the same ID for CustomTab. The display name of your add-in. To hide the ribbon, at the right edge of the ribbon, select the ^. Cancel. We have one add-in created in word long back, now we are doing some modification in the custom tab(Add-ins shown in below screen shot) 1. i don't know how to solve it. From the Manifest.xml file I am triggering events to JavaScript function through ExecuteFunction JS function is getting hit, but there is no update happening on the TaskPane UI. Manifest.xml While there is no longer a support website or central distribution link, you can get it from the link above. Adding Commands. An example of an add-in program might be a program designed and distributed by your company's IT department to highlight company names in any document you open on your computer. To add commands to a group, you must first add a custom group to a default tab or to a new custom tab. Office ribbon is providing rich UI and you can add your own custom tab on it very quickly. you can't "share" Ribbon components using the Designer, it can only be done using Ribbon XML. Used on the store and various placed of the Office UI such as the add-ins dialog --> < DisplayName DefaultValue = " Add-in Commands Sample " /> < Description DefaultValue = " Sample that illustrates add-in commands basic control types and actions " />