both are claiming that flash is not installed (even if it is and all other flash sites are working)

What Zenphoto version, player plugin version and browser are you using?

I have the same problem.
I tried: IE7/windows , firefox/windows and firefox/linux with flash installed and working on other websites.
I use the night build zenphoto-2008-09-04-trunk

Thanks for your help

I am sorry, I can't reproduce it. Do you get any errors in your log maybye? Do you really have the right plugins? Please also note that only one player should be activated at a time. And a link to the site would help.

in the log?
only one player plugin activated: flowplayer
right plugins? I downloaded the night build
here is the link to the video page:
http://varnikabhanga.online.fr/index.php?album=video_test&image=ubuntu_small.flv

thanks for your time

Sorry for asking "annoying" questions, but sometimes users don't overwrite all files and have partly older ones.

Well, I can indeed reproduce this with flowplayer, but only in this theme (stopdesign). We will investigate that.

Sorry, we did some research and somehow the flowplayer plugin does not work with the stopdesign theme. But for us the flvplayer does work. So please try that for now. I will open a ticket so that we don't forget about this.

flvplayer works indeed.
Thanks you very much