问题
My add-in has a MessageComposeCommandSurface ExtensionPoint that adds a button to the ribbon when the user is composing a message. I expected the button to always be enabled when it is visible (e.g. when the user is composing a new message or replying to an existing one), but sometimes it is greyed out/disabled and I'm not sure why.
Does anyone know the exact circumstances for when an add-in ribbon button is greyed out/disabled?
回答1:
Try to disable some COM add-in and then enable it again. In my case it helped to make buttons active.
来源：https://stackoverflow.com/questions/46697093/outlook-add-in-command-button-disabled-when-composing