This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Since upgrading to Firefox 5, I am unable to open PDF's in my browser. Obviously this can present quite a problem.

  • 5
  • 80
  • 13 views
  • Nzaghachi ikpeazụ nke dc_07

more options

When I try to open the pdf, I get this message:

"The Adobe Acrobat/Reader that is running can not be used to view PDF files in a web browser. Please exit Adobe Acrobat/Reader and exit your Web Browser and try again."

When I try to open the pdf, I get this message: "The Adobe Acrobat/Reader that is running can not be used to view PDF files in a web browser. Please exit Adobe Acrobat/Reader and exit your Web Browser and try again."

All Replies (5)

more options

I haven't heard of any similar message before. In your "More system details..." it lists two different Adobe PDF plugins, version 8 and version 9. You may have a conflict there, especially if the older one isn't disabled. You could try to disable it here:

orange Firefox button or Tools menu > Add-ons > Plugins category

---

If that doesn't help... Adobe Reader and the plugin have been updated to version 10. but Are you willing to upgrade Adobe Reader to see whether that fixes the problem?

http://get.adobe.com/reader/

more options

Exact same problem here.

Firefox claims Adobe is already running and IT IS NOT!

I am using VISTA (CRAP) sp2.

I have had nothing but problems with VISTA. It will NOT network with XP or anything else XP. It is the most horrible OS from Micro$oft ever! Win 3.1 was OK, Win 98 was better, & Win XP was good except for not being able to do multi-session CD's.

So we either have a Firefox problem or it is the OS.

Now you've heard of a second identical issue.

My solution was to right-click and download the PDF. Then open it in Adobe Reader.

There are other issues with this new Firefox that I did not have with the older version but they are tolerable.

more options

Problem fixed. I disabled old versions of adobe reader plug in and downloaded Adobe Reader X. Works fine now.

more options

Cannot find Adobe Acrobat/Reader in the add-ons.

I have v9 & horrible M$ VISTA and it does NOT work with Firefox 5.

more options

Had same problem. Followed all Firefox recommendations about plug ins etc etc with no result. In the end uninstalled Acrobat Reader (think it was v9) and re-installed from their website ( Adobe Reader X (10.1.0) ). All good now. Took seconds, wish I'd done that first.