My easy solution to the actual question...
My easy solution to the question is just check your mail using the web app for your companies exchange server. For my company anyway, I can read an email message online and there is a link on the page that I'd have to click to send the read receipt. It appears that I can log out and log back in just fine and still have the read receipt option there.
Now of course, that isn't taking into account the whole 'to send a read receipt or not to send a read receipt, that is the question' part of this thread. I wonder how many of the frequent users of the read receipt had Novell Groupwise somewhere in their past. We finally moved to Outlook in the last year and I am surprised how many of our users have complained about not having the read/forward/delete trail like they were accustomed to in Groupwise.
Generally, I really don't have a problem with read receipts as long as the original sender uses it right. It is not OK to request a read receipt by default on every email (one user that I know about in my company does this). It is also not ok to assume that receiving a read receipt means that I am answering the email right away. I don't really have any users that do this. I might have some research to do or am working on something else at the moment. I usually do try answer emails fairly quickly though. I figure I can't complain about other people taking forever (a couple of hours) to answer an email if I don't make it a habit of answering fairly quickly.