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What happens when you install, any Error ?
Which processor do you have on your MAC ? (Click on Apple button -> About this MAC)
The processor is 1.83 GHz Intel Core Duo. When I press on the Flash player icon, it says install . When i click on it, up pops a screen that says :
This is an app from the internet. It is on the disk image "install-flash-player-osx-4.dmg". Safari downloaded this disk image on Mar.15, 2013. (however, I just did it again and it said it was downloaded yesterday at 9:27 am from get-adobe.com)
At the bottom of the page , it says show web page cancel open. When I press open, a page pops up and at the top ,it says Adobe Flash Player 11.6 Installer. At the bottom of page , it says quit ( in white) and install blacked out.
Now when some one send me a youtube, I can open it if I press quick look but if I press the youtube site, I only get a black screen.
I don't know what I have done- not anything, but now I am able to open you tubes.