You must have the Adobe reader on your computer to open these Newsletter files. If you do not have Adobe reader you can download it free from Adobe.
When the Adobe download page opens you should unclick all options to install additional software on the download page before you click the "Install Now" button. Those options are currently as follows:
Install the Acrobat Reader Chrome Extension
Install Google Chrome
Install Google Toolbar for Internet
Download Free Adobe Acrobat DC Reader
You can also download these files by right clicking the one you want then selecting "Save target as" from the pop-up menu and follow the operating system instructions.