I am having the EXACT SAME problem, same message, I can not open a PDF file online. My Tech told me to Delete my Adobe and reinstall. Didn't work.
I work with a lot of genealogy files, and most of them online are in PDF, so when I Google something, a lot PDF files show up, but when you click on, I get the ERROR message as you.
Tells you to Debug by clicking RETRY. That does not work either, and you can't back out of this. Mostly I have to just X out of the internet and start over.
I even tried to reset my system to an earlier time, still did not work.
There are a finite number of possible problems. The solution will present itself but only after ruling out the impossible (to paraphrase Sherlock Holmes).
1) Are the PDFs corrupt? Probably not.
2) Is your version of Acrobat or Adobe Reader out of date or corrupt? Acrobat Reader is free - the most current version can be found at http://ninite.com
3) Instead of viewing the PDF in the browser, download it to your Windows desktop. Once downloaded, double-click it open in it in Reader. This takes the browser out of the equation entirely since you are simply opening a local document.
4) Assuming you are using Reader (the free version that does not allow editing/creation of PDFs) then uninstall and reinstall Reader and attempt to view PDFs in browser again.
In addition Ccleaner from http://piriform.com will clear temp files and other junk. Run it (save your browser cookies however) and attempt the process again.
Several programs are no longer playing nice with each other.
Several of the insane rapid release FireFox versions have had problems with PDF files.
Now, I just download the PDF and then open it in the standalone PDF viewer. [I use PDFExchange, rather than Adobe.]
I have had similar problems with IE and FF.
Adobe Flash would not work with the FF rapid release version 13.
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I cringe every time I see software ‘upgrade’ or ‘update’ recommendations. Upgrades/updates seem to create more problems that they fix.