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abobe acrobat/reader that is running can not be used to read files in a web borswer...why?

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i am trying to use adobe reader. when i try to see a pdf i need for school i get" the adobe acrobat/reader that is running can not be used to read files in a web browser. i have tried uninstalling and reinstalling by i cant..get a cryptic message there too. tried to go to adobe and add a fix but get " this patch package could not be opened, verify that the patch package exists. i have also done system restore twice to times when reader was working to no avail. i have spent many hours on this and am frustrated beyond belief. the adobe site gives complex registry help info and many warnings and microsoft utility clean ups links which also will not run. can anyone give concise easy to follow sure bet solutions?

This happened

Every time Firefox opened

== asevral days ago when trying to read a pdf for university work assignment

i am trying to use adobe reader. when i try to see a pdf i need for school i get" the adobe acrobat/reader that is running can not be used to read files in a web browser. i have tried uninstalling and reinstalling by i cant..get a cryptic message there too. tried to go to adobe and add a fix but get " this patch package could not be opened, verify that the patch package exists. i have also done system restore twice to times when reader was working to no avail. i have spent many hours on this and am frustrated beyond belief. the adobe site gives complex registry help info and many warnings and microsoft utility clean ups links which also will not run. can anyone give concise easy to follow sure bet solutions? == This happened == Every time Firefox opened == asevral days ago when trying to read a pdf for university work assignment

All Replies (3)

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Do you have multiple versions of Adobe Acrobat Reader installed on that PC? Or maybe Acrobat Reader and the full Reader program, but differing versions?

See these articles. https://support.mozilla.com/en-US/kb/Using+the+Adobe+Reader+plugin+with+Firefox

https://support.mozilla.com/en-US/kb/Opening+PDF+files+within+Firefox

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sorry.. i am not an expert and am exhausted with this mess. most of the articles make no sense to me. and some refer to explore etc.

i am about to just get rid of firefox..it has caused issues in other areas too and may requests for help have gone unoticed..as i said am EXHAUSTED?HEADACHE and all this tech stuff is absurrd...sorry.but i am lost and tired.

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You can check the "C:\Program Files\Mozilla Firefox\plugins" folder to see if there is a nppfd32.dll file in that folder.

You can see the installed plugins on the about:plugins page. If you set the pref plugin.expose_full_path to true on the about:config page then you see the full path of plugins on the about:plugins page. It is best not to leave that pref set to true as it exposes that full path to web servers, so reset that pref to false after you are done with the about:plugins page.

You can open about:plugins and about:config via the location bar, like you open a website (about: is a special protocol to access some build-in pages). If you get a warning when opening the about:config page then you can confirm that you want to continue.