1. Uninstall the current Adobe Reader you have installed
2. Download and install the latest version of Adobe Reader.
3. It is preferable not to open the file inside the browser window. Save the file to your desktop. Open the file afterwards directly with Adobe reader.
4. Make sure the PDF file downloaded completely.
   
5. For various other problems related to opening, viewing or printing PDF files, we suggest you visit the Adobe site for solutions: http://www.adobe.com/support/reader/

If none of the above resolve your issue, please complete an Error Report form, so we can look into the problem.