Opera

If the Adobe Acrobat Reader plug-in returns the error message "Could not find Acrobat External Windows Handler" when trying to view a PDF document, you can try to uninstall and reinstall Acrobat Reader. Get the latest version from this page:

http://www.adobe.com/products/acrobat/readstep2.html

You can find more information about the "Acrobat External Windows Handler" error in Adobe's Support Knowledgebase.