I had flash player a few days ago. Now I keep getting plug-in failure. I've tried for hours today to download... You tube won't play either. Your site says I have latest installed but I can't see it in my launchpad
You won't see it in LaunchPad.. It's NOT an app. It's a plug-in. It installs to Mac HD/Library/internet Plug-ins.
Try doing a full clean install:
How to perform a "clean install" of Flash Player in Mac OS X
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