The same .ics attachment has been sent to two different users. Upon opening the email, the first user has "accept" "tentative" and "decline" buttons. Upon opening the email, the second user has no buttons, but can view the .ics attachment with option links for "add to briefcase" and "download". The first and second users are on two separate servers with addresses on the same domain. Features, Preferences and Advanced Settings have been matched for both users. However, the second user can still not accept .ics formatted meeting requests through ZCS. Strange behavior, we need buttons I tell ya!
Thanks for your inquiry, and any possible suggestions