This happened not too long ago.. basically my friend Psychic-Kirby was sending me the installation file to the new MSN Beta (for some reason I couldn't download it) and, as you may know, because MSN doesn't tolerate sending .exe files as they're "potentially unsafe", it brought up the send error message - in a completely different messenger window I had left opened for hours.

o_O I really have no idea why it did that; the other person doesn't even know who Psychic is, and he was offline when this occurred. One of the most unusual glitches I've ever seen.....