Here is additional info: User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:2.0.1) Gecko/20100101 Firefox/4.0.1

You need 64-bit version of Flash for starters as you are using 64-bit Firefox 4.0.1. http://labs.adobe.com/technologies/flashplayer10/square/

A easy way to get Firefox and also SeaMonkey if you ever use it to detect and use Plugins is to put the plugins in a folder called plugins in /home/username/.mozilla/

I already installed this particular plugin, but it does not work for me.

Oh thank you for the not helpful reply...

You have not said what you actually have installed in first post and where you have tried installing them and have you tried the suggestion I made in putting it in created plugins folder where I suggested.

Could be a permissions issue depending on where you put the plugin if not in /home/.

Dear James,

Sorry to have offended you; I did not realize that the reply rating has a personal effect, as in a social network. Live and learn,,,

I just tried following your advice to the letter: removed the plugin from the root location, created a directory in /home, and put the plugin there. The browser did not notice the changes: the slash plugin showed on the list of firefox plugins, but there was no flash activity, neither at NYTimes.com bor youtube.com.

 Amnon

Are you running a 32 bit version of Firefox or a 64 bit version of Firefox ?

The Flash player shows as installed in your More system details list

• http://www.adobe.com/software/flash/about/

Running 64 version -- see:

 Here is additional info: User -Agent: Mozilla/5.0 (X11; Linux x86_64; rv:2.0.1) Gecko/20100101 Firefox/4.0.1 

The menu in the browser shows shockwave flash 10.3 d162

However on the page

 http://www.adobe.com/software/flash/about/

my flash plugin is not detected!

The Linux x86_64; only means that you have a 64 bit OS. You can still run a 32 bit Firefox version with that setup. A 32 bit Firefox version needs 32 bit versions of plugins.

You wrote that the previous Shockwave Flash 10.0r42 version worked and that is a 32 bit version, so that would imply that at least at that time you were running a 32 bit Firefox version.

I checked my system again.

For firefox I got these details from the "software manager":

 firefox 4.0.1-1.2 (x86_64) installed

I then got rid of all flash versions, and copied a fresh copy of the file

 libflashplayer.so

extracted from the package

  flashplayer10_2_p3_64bit_linux_111710.tar-1

that I got from

 http://labs.adobe.com/downloads/flashplayer10_square.html

into the directory

 /home/amyekut/.mozilla/plugins 

Now my browser now says under "plugins":

  shockwave flash 10.3 d162 2010-11-17

Is this the expected listing?

Finally the flash does not work, as before. See attched photos.

 A.

Today I installed chrome and it runs flash perfectly!

I had the same problem on firefox 5,0. I had to install libpcre0-32bit and nspluginwrapper then run nspluginwrapper -i 'path_to_plugin' to register Flash. The same procedure is requires for the Adobe reader plugin to work.

nspluginwrapper allows plugins compiled for i386 in Mozilla on Linux/x86_64 or other architectures. You also need the 32 bit version of libraries compiles for x86_64 for some applications and plugins to work 0n x86_64 architecture installations.