The information in this article applies to:
Microsoft recommends that users using assistive technologies such as ZoomText should use Internet Explorer and Adobe Reader as their default web browser and PDF viewer.
In the search field next to the Start button type in "Default Programs"
Hit the enter Key on your Keyboard
Select "Set your default programs".
Select "Internet Explorer"
Click on "Set This Program as Default"
Click on the OK Button
Next download and install Adobe Reader 11 from the link below.
During the setup There is an option to set Adobe Reader as your Default PDF viewer. Make sure that is checked.