Here is my amswer on this topic from another forum:

What is supposed to happen is this: A meeting request comes in to you

inbox. The "sniffer" process will, at some point, see the request and
put a Tentative item on your calendar. At a later time, you can make
your response choice about the request from either the email request o

from the calendar item. The preferred method is to respond from the
email request, because that will appropriately notify the meeting
organizer.

The only thing that I know of that disrupts this process is whe
someone
has set up a rule which moves meeting requests to another folde
besides
the inbox. In this case, the sniffer won't get a chance to see the
request, because it only scans the inbox. A rule could do this if it i

set up to move "All messages from John to the John folder," fo
example.
In this case, when John sends a meeting request, it will get moved ou

of the Inbox, and not added tentatively to the calendar by th
sniffer.

A way around this could be to add a rule at the top of the Rules list
which would:

"Apply this rule after the message arrives
uses the Meeting Request form
stop processing more rules"

When this rule is applied first, all meeting requests will stay in
the Inbox

-
jmlyl