Why isn't Youtube working on my kindle fire?
I watched some youtube videos on it earlier this week, but it keeps saying "plugin not supported" and "not available on this device" now.
Update your flash player to solve the problem
Chances are there's chance on the YouTube site, that's why it worked but now it doesn't. Try other ways to access Youtube on the Kindle and see if it works.
Here's a good discussion on various ways of accessing Youtube on the Kindle tablet. There should be some way that will work: