Hi AndreaC
There are a few features within Adobe Acrobat that can be changed that will allow you to print your PDF files again. To make these changes, please follow these steps:
1. Open your PDF in Acrobat Reader.
2. Click on Edit and then Preferences.
3. In the left hand pane, click on Security (Enhanced).
4. Remove the checkmarks from "Enable Protected Mode at startup" and from "Enable Enhanced Security".
5. Close Acrobat Reader.
6. Open your PDF again with Acrobat Reader.
7. Click on File and then Print.
8. Click on the Print button.
Your PDF file will now print.
If you continue to have difficulties, please contact our support group using the following link:
http://Canon.us/ContactLI