If you have just updated your Mac system to Yosetime, (10.10.3), and were using an older document producing program, such Apple Works, you will have to update the program to view, edit and print your AW docs.
The recommended program to use is LibreOffice. It is a free upgrade and will read all AppleWorks 6 documents. However, you will have to open the AW docs for the first time using the program. In other words, do not try to click on the document shortcut as they are set to open with the AW and not LibreOffice.
To get LibreOffice, go to google.com and type it in the search bar. Click on the link to download the Free Office Suite. Follow the installation instructions and begin using the software. With a good connection the entire process should take about 30 minutes to download, install and use.