Problem with Safari, Firefox and Flash

I am having a problem with Safari (6.05) and Firefox (23.01) with Flash. When I try load up any YouTube videos I get a 'Plugin Failure' message. I'm on OS X 10.8.4

When I open them up with Google Chrome everything is fine.

I tried updating my Flash with Safari and Firefox, but the download would just not begin. So I went to Chrome and it came up with a message saying that Flash is included with Chrome. I then realised it was a Flash issue with Safari and Firefox, but I couldn't download the latest Flash with them. So I had to download the Flash installer with Chrome and then run it.

So after installing the latest Flash I still keep getting the 'Plugin Failure 'message.

I have uninstalled any extensions in Safari and Firefox. And I have also made sure that I am not signed up for the HTML5 test on YouTube (after many google searches I see this is a common problem with other users.

If anyone can help that would be great. Even though Chrome is all working fine, I prefer to use Safari and Firefox.

 

Check out the post here on the Apple forums that gives suggestion on how to solve it by using an archived version of Flash.

https://discussions.apple.com/message/22954203?ac_cid=tw123456#22954203

Use the debug version.

also make sure to use the uninstaller with the DMG to fully uninstall Flash before installing the debug version.