Zoho Webinar not sending calendar entry into Outlook or other calendars

Zoho Webinar not sending calendar entry into Outlook or other calendars

Dear All,
I am using Zoho Webinar for last few months and noted that when a attendee registers at the webinar link he gets an email will intimating his registration and link to webinar. He also get few file ( for Outlook, Google calendar etc) which he can download and open the respective calendar and save there. But he is not getting invite which he can accept to create a entry in his calendar. This feature is working in meetings and surprisingly even on cancellation of webinar such entry comes. When I reported to it to support they say there is no such feature.  How  it is working in case of webinar cancellation and meeting invites.  Any one using zoho webinar please share your experience and do you also face this problem.