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Firefox does not recongize plug in already on the computer.

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I had Adobe Flash Player 11 Active X (11.9.900.170) installed on my computer before downloading and starting to use Firefox. I went to a web site, and Firefox is telling me a plug in is needed to display the content of 2 windows on the web page. I used the "Install plugin" link, but the automatic installation failed. I then did the manual installation. I now have art of the Adobe 11 Flash Player Plugin (11.9.900.170) installed as well. When I go back to the web page, I am still getting the same error message. When I try to install, it is telling me to install the same plugin (& version) that is already on my computer. Why isn't Firefox recognizing what is already on my computer? Thank you.

I had Adobe Flash Player 11 Active X (11.9.900.170) installed on my computer before downloading and starting to use Firefox. I went to a web site, and Firefox is telling me a plug in is needed to display the content of 2 windows on the web page. I used the "Install plugin" link, but the automatic installation failed. I then did the manual installation. I now have art of the Adobe 11 Flash Player Plugin (11.9.900.170) installed as well. When I go back to the web page, I am still getting the same error message. When I try to install, it is telling me to install the same plugin (& version) that is already on my computer. Why isn't Firefox recognizing what is already on my computer? Thank you.

All Replies (2)

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Have you tried deleting the pluginreg.dat file in the profile folder.

SEE: http://kb.mozillazine.org/Flash#Testing_Flash and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

They both include instructions for deleting the file and refreshing the plugin list.

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Firefox doesn't use ActiveX, it needs the NPAPI version of Flash.

http://get.adobe.com/flashplayer/