Can't finish previewing. There isn't enough memory. ID = -108

We run CS5.

One of our clients sent us a file that they would like printed.  The file is 1MB in size, and in PDF format - nothing unusual about any of this.  As usual, I saved the file and tried to open it in Illustrator to set up a proof for our customer, and to check and make sure the file is print-ready.  I received the error: "Can't finish previewing.  There isn't enough memory. ID = -108".  I press OK and it opens up a blank file with some crop marks on it.

I've tried finding a solution online, but everyone who has this problem seems to have next to no RAM.  I'm running on a brand new computer with Windows 7, 16GB of RAM and the Intel Core i7 processor.  I didn't think my RAM or cache were the problem, but just to be sure, I shut off the computer, let it sit for a few minutes, and started it up again.  Same problem.

I am able to open the file in Photoshop and Acrobat - but even when I save the file at a lower resolution, and turn it into a jpeg, it still won't open.  I get the same error.

I need to be able to work with this file.  How can I resolve this?

Thanks!