We have reports of trouble reading recent Newsletter pdf's in some browsers.
Simply trying a different browser (Firefox, Safari, Opera, Chrome, etc) may be the easiest workaround.
As far as we can tell, the problem only appears using Internet Explorer.
Evidently, we are passing through an era of incompatibility between Microsoft's Internet Explorer browser and Adobe's Acrobat Reader, which handles pdf's. This problem is fairly well known. A variety of geeky "fixes" are also available, including upgrading to the latest version of Acrobat Reader X.
We're sorry for the inconvenience.