I found this link Cancel outlook meeting requests via MailMessage in C# and I tried as it suggests, it sends the cancel outlook meeting request but when I do 'Remove from Calendar' on outlook, it doesn't remove the meeting. Please share any work around or solution. Thank you.
The following link should help you. UID for vcalendar has to be the same one in order for the calendar to be removed. If you do UID= Guid.NewGuid(), it won't remove the calendar. The good idea would be to save the UID somewhere so when you send the cancel appointment request use the saved UID so that it will remove the calendar from client's outlook.
How can I programmatically cancel an outlook meeting with asp.net VB?