This is a fresh installation of Illustrator. I just tried exporting a page from Sibelius 7, and that EPS opens properly in Illustrator as well as the other aforementioned programs. Although Sibelius...

And EPS files display just fine for me, in every program, it seems, other than Illustrator. Strange... Hope this helps someone in the future.

@Wiggy, maybe right-click and "Save As"? I have no problem opening them on other systems. Is anyone else having problems opening/saving the links? Ok, I figured out the problem, at least for me....

PDF and EPS look perfectly fine. Both open just fine in Photoshop CS2, the EPS opens as well in IrfanView 4.30 without problems. Here are links to both files: EPS PDF ...

Wiggy, tried with both EPS and PDF. Illustrator shows gibberish for note heads and other elements as the OP indicated.