From what I could find, it would seem you trying to open PDF's through Firefox.
First step that you should take is run the Adobe Cleaner Tool http://www.adobe.com/support/contact/...
Next you should check the following
In Firefox go to Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available" and disable it if it is enabled.
If the Firefox fix doesn't work, delete the profile you are using and create a new one.
Then test to see if the problem is solve and if it doesn't fix it, the text step would be the following:
- Lauch Adobe Reader
- From the menu, choose Edit -> preferences -> General
- Uncheck the option for "Enable Protected Mode at startup"
Then run another test in your browser to see if it works
If none of these work, uninstall the program, run the cleaner and the reinstall it and see what happens.