Please provide more details so that we may be able to assist you.
What does 'not working' mean? What happens when you try to view Flash content?
What is the OS version, browser type and version.
Do you have Flash Player currently installed, if so what version?
What steps did you take to install Flash Player
I was running Flash Player 11. All systems go. Web sites ran flash videos with no perceived problems.
A popup said there was an upgrade from Adobe. I clicked the link and installed Flash Player 12 from the web site. Now, if a site tries to run anything that requires flash, I get a message that my machine does not have the Flash Player.
I’m running Windows 7 (32-bit). I’m presently running Internet Explorer version 11.0.9600.16476, Update version 11.0.2 (KB2898785). When I check the add-on manager, it tells me I have Shockwave Flash Object, Adobe Systems Incorporated, Enabled, Version 18.104.22.168
The Flash Player install seemed to proceed normally, with no glitches. I can’t figure out why web sites cannot find the flash player. Can you help?
MS really did a number on IE 11. They intentionally screwed up the User-Agent Strings so it's difficult if not impossible for websites to identify.
The pages can't recognize the browser, so they don't recognize any of the plugins, like Flash Player. So far, Microsoft has made NO indication that they have any plan to fix it soon. In fact, the loonballs in Redmond actually think this was a good idea.
Microsoft's recommendation is to use Compatibility View for affected pages, and "pretend" you're using an different browser. Trouble with that is it has seen limited success at best, and you have to individually enable it for EVERY page that has problems.
I'm not big on "pretending" so I recommend actually using another browser.
ANY of those will work where IE11 won't, with the Flash Player Plug-in (For all other browsers), and Chrome doesn't even need that because it has its own Flash Player plugin built in.