Currently Being ModeratedNov 13, 2012 1:43 PM (in response to Kiran AK)
1.Are Plug-ins Enabled?
Safari > Preferences > Security
Check the box for Enable Plug-ins.
2. Check whether you are currently in YouTube HTML 5 trial.
At the bottom left of the page uncheck the box for
"You are currently in the HTML5 trial".
3. Reset Safari.
Click Safari in the menu bar and select " Reset Safari".
When the reset window opens up, click "Reset" button.
4. Empty Safari caches.