Mmmm. I certainly believe you, but a file not opening when it specifically asks you to open it doesn't make sense.
And what's odder is that you didn't seem to have this problem back in December '07 or '08.
Have you or someone else made changes to your computer in '09?
Also, does the pop-up with the extra smileys come up for you? If it does, there shouldn't be a reason why the attachments don't. But then, when it comes to IE, I've come to expect almost anything...