I created (by RibbonDesigner) new outlook ribbon that appears in the window of an appointment.
RibbonType: Microsoft.Outlook.Appointment,Microsoft.Outlook.MeetingRequest.Read
I want to add this Ribbon to CalendarItems near 'Appointment' tab , when appointment is selected from the calendar view
[Location where I want to put the ribbon]1
How can I do it?
The ribbon designer doesn't provide all the features of the Fluent UI, in some cases you need to use the Ribbon XML to get things working. See Walkthrough: Creating a Custom Tab by Using Ribbon XML to get started quickly.
Looks like you need to add a new contextual tab to the Calendar Tools of the Explorer window. For example:
<contextualTabs>
<tabSet idMso="TabSetAppointment">
<tab id="YourTab">
...
</tab>
</tabSet>
</contextualTabs>
Read more about that in the similar forum thread - How to get Calendar Tools Ribbon through VSTO Outlook Addin.
You may also find the Chapter 11: Creating Dynamic Ribbon Customizations (1 of 2) article helpful.