Hi - Our HR department needs to be able to put a mandatory appointment on all users calendar. They want the end-users to be UNable to accept or reject; we just want the appointment to be there. Any suggestions? (I am not a programmer.) This is Exchange 2007, Outlook 2007 & 2010. Thanks!

You could use Exchange Web Services to do this. I would ask in the Dev Forum.

You could also create the item in a PST and use import-mailbox.

Great idea Chris!