Specifically, which browser are you using? (Internet Explorer, Firefox, Chrome, Safari, Opera, etc.) Have you tried another? Also, what security software do you use?
Flash Player can be corrupted, requiring more than a reinstall, but it could also be a scripting issue, with the browser or your security software.
Let us know.
John
I'm running Vista on an Acer PC. I've had the computer since March '09, and it has always played videos just fine. Since about 3 weeks ago, streaming video from sources such as youtube.com, cnn.com, etc. will not play. Media Player is fine, I've re-installed adobe flashplayer, but nothing seems to work. I need some help, in layman's terms please 
I'm quite handy with the computer, but am not uber-familiar with technical jargon. Thank you for your help.
as an addendum, when i click a video in youtube, etc., i get a black screen, with no sound, no picture. Please help
Chowhound
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