Many people are experiencing a problem in which YouTube videos and other Flash content will not play in Firefox. Instead a message appears which says:
“An Error Occurred. Please Try Again Later.”
User forums abound with pleas for help, which are either answered incompetently by support personnel or ignored altogether.
I tried so many things to fix this. I re-installed Flash, disabled many plug-ins, ran CCleaner to purge the browser, re-installed Firefox with personalization retained then deleted, and scoured the unhelpful forums.I even ran a clean-up scan of my registry, which I hate doing. It makes me nervous because making changes to the registry can cause serious problems.
For me, the issue turned out to be a conflict within Firefox between Flash and RealPlayer. The solution was to change the settings in RealPlayer as described in the Adobe Forums at http://goo.gl/1C7rA.
If you have the problem and are using an alternate browser, you can watch this video demonstration of the repair: