Hi all ,
i tried to install flashplayer plug in on firefox 15.0.1 , but it cant.
folowed instructions on readme.txt.

So downloaded install_flash_player_11_linux.i386.tar.gz
there was in archive libflashplayer.so and /usr
after than
tar -xzvf install_flash_player_11_linux.i386.tar.gz
cp libflashplayer.so /usr/lib/firefox-15.0.1/components (in this directory found all .so files)

and in the end typed
sudo cp -r usr/* /usr

after than started firefox , typed aboutlugins and had nothing.
My distro is Slackware 14.

First off, the current version of Firefox in Slackware 14 is 18.0.1. So are you using FF 15.0.1? Or did you mean to type FF 18.0.1?
If you are using FF 15, you should upgrade to FF 18.0.1 ASAP.

In any case, here is how I installed flash 11.2 on Slackware 14 as root:
Note that I am using 64 bit Slack 14. So if you are using 32 bit Slack 14, the path will be /usr/lib/mozilla/plugins/
This will untar the flash .tar.gz and copy the /usr directory and libflashplayer.so that are created from the flash .tar.gz to your /usr/lib/mozilla/plugins/ directory.
Remove the flash stuff that you copied to /usr/lib/firefox-XXX/components/ directory and the stuff you copied to your /usr directory first to avoid potential conflicts.

There is also a slackbuild for Flash that you could use for this: http://slackbuilds.org/repository/14...player-plugin/

As tommcd said, you need to update first. So, if you haven't already done this, do it now. As root, uncomment a mirror in /etc/slackpkg/mirrors, then run:
then:
then:
Then either get the SlackBuild tommcd suggested, or a package from here:

http://connie.slackware.com/~alien/slackbuilds/

Thank you

Download the file flashplayer-plugin-11.2.202.261-i386-1alien.txz from this link
http://connie.slackware.com/~alien/s...ugin/pkg/14.0/
the on therminal cd to the downloaded file and type
Thanks AlienBob for sharing

Good luck to you