Are you pressing your alt key to go into the menu to accept the invitation?
With previous versions of Outlook the accept button was in the body of the
message but with 2010 it's in the menu.
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Have questions about that IPhone, IPad or IPod Touch?
I'm not sure why you might be having trouble reading the body of the
message, but I can tell you how to accept, decline or respond tentative.
After you read the invitation, close it and return to the inbox, or where
ever the invite is residing. While focused on the invite in the inbox,
press the