flashplayer not recognized by youtube/tweetdeck

Hey everyone, I'm using a macbook pro for the first time and it seems like I'm having a problem with adobe flashplayer. I have downloaded its latest version and install it correctly but when opening youtube or trying to download programs such as tweetdeck they don't seem to open and require a flashplayer upgrade again.
What do I do? Please help. thanks

Did you restart the computer?
Same thing happened to me.

What browser are you using? Have you checked your browser's settings to see if the plugin is recognized?