This tutorial shows how to respond to meeting requests on OWA Calendar
When you are invited to a meeting, you will receive an email, and Outlook will automatically add the meeting as Tentative in your calendar. The email invitation you receive contains a snapshot of your calendar on the day of the proposed meeting. This saves you the trouble of checking your calendar for potential conflicts.
Whether accepting or declining a meeting, it is important that you ALWAYS send a response to the requester. If you do not do this, the requester will not be able to see whether you plan to attend.
NOTE: After you respond to a meeting invitation, Outlook automatically moves the email to your Deleted Items.
To respond to a meeting request, all you need to do is click one of the buttons in the request. When you do this, a meeting response is created and sent to the meeting requester. You have several options: Accept, Tentative, Decline and Propose New Time. Once you make your selection, a meeting response is created and sent to the meeting requester.