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

  • 5 replies
  • 80 have this problem
  • 13 views
  • Last reply by dc_07

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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)

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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

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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/

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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.

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

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

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

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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.