You might encounter some system related problems which might stop you from downloading PDFs. Here are a few tips for troubleshooting:
1. Install latest version of Acrobat
The latest version of Acrobat Reader can be found on Adobe's website at http://www.adobe.com/products/reader
Once the link or icon is selected, you will have to specify your language, operating system, and connection speed. Once you have completed these steps, the Adobe Reader software downloads and installs automatically on your system. Before you install the latest version, ensure that your system meets the requirements.
Please note that you should ideally do a clean installation of latest Acrobat Reader version. This means that you should not install a newer version on top of an older version. This is known to cause problems. Instead, first uninstall the older version, then install the newer version.
2. Run Acrobat with no other applications running in the background.
Some applications that run in the background might cause problems when running together with Acrobat.
3. Plug-in related problems
Plug-ins are tools used to extend or add specific functionalities of your web browser. Acrobat Reader is one such plug-in. Other plug-ins, especially those that also deal with PDF files, may affect Acrobat Reader. Try to run Acrobat without any other plug-ins running.
4. Check the size of the document you are downloading
Ensure that the size of the document is reasonable. There might be problems downloading documents that are greater than 2Mb.
5. Check whether the document has non-English fonts
Check whether document you are trying to download has non-English fonts. If there are non-English fonts . embedded or linked, the fonts may need to be downloaded and installed to view.
6. Documents not opening when viewing via the web
If documents are not opening when viewing via the web, then from the Edit/Preferences/Options Menu, untick the box Display PDF in Browser.
7. Ensure your system meets the minimum Acrobat requirements.
Verions and requirements change frequently. For a few list of versions and requirements, please visit http://www.adobe.com.