I have the same problem and Im getting really tired of it. I have tried everything i have read update, reset, safemode, old version new version. delete stuff add stuff. the only thing that works it using another Browser. If I have to use a separate browser to watch flash stuff I will just have to switch its a pain in the ass. My life is stressful enough with out having to deal with then when I want to watch a youtube video Im ready to give up.

Hi kicker1911, what happens when you try to play a video on YouTube? For example: black box, "loading" indicator spins endlessly, crash inside the plugin, etc.

If you run Windows Vista or newer, disable the Flash Player plugin's protected mode. See this support article from Adobe under the heading "Last Resort": Adobe Forums: How do I troubleshoot Flash Player's protected mode for Firefox? Note that the folder in which you make the edit depends on whether you run 32-bit Windows (C:\Windows\System32\Macromed\Flash) or 64-bit Windows (C:\Windows\SysWOW64\Macromed\Flash).

Kindly check the discussion here: https://support.mozilla.org/en-US/questions/960915?page=2#answer-469858 Also post ur comments on the same.

youtube freezes video and the whole browser seems to freeze unless I move my mouse around... its like it wakes it up ... I tried all that stuff you mentioned plus everything else I could find. I have a feeling its in the code not a setting. I run Win 7 Pro I have been using FireFox for years and every few years there is a problem that I get tired of and I stop using i,t then I come back later and its fixed. Last time was fire fox just kept freezing up every 2 to 5 min. Tried all the work around and nothing worked so I just stopped using it for about a year. then tried it again...been using if for a few years now the flash problem. Thank you for the reply

I would be happy with... "We know there is a problem and we are working on it we thank you for your patients and for supporting FireFox.." I dont pretend to know that its fire foxes fault, but then again thats not my problem I just want to watch a Youtube video will Im doing dishes and not have to dry my hands off every 20 seconds and go move the mouse.

Hi kicker1911, it's not possible to read every thread here, but honestly I cannot remember anyone having to move the mouse every 20 seconds to prevent Flash or Firefox from freezing.

I'll think about it and hopefully someone will have an idea.

I have the same problem, and I have tried all the troubleshooting and checked other support articles and users with similar problems, but still no luck. (Windows 8, on a new sony i7 laptop)

All plugins are up to date. Internet Explorer plays all these files without any problem, so I know it has to be Firefox issue or bug.

For example, I cannot play this video on Firefox, but it plays on IE:

http://autos.yahoo.com/blogs/open-road/top-five-sleeper-cars-video-205832307.html?vp=1

It's not only Yahoo video...

Another round of web-sites where Firefox 23.0.1 can not play the video:

http://www.bbc.co.uk/news/world-middle-east-23792641

The BBC "waiting circle rotatory" displays, then the BBC reports the error.

The FF Error console reports:

EMP v.3.1.0.r749603_749269_749444_6

Playlist URL : http://playlists.bbc.co.uk/news/world-middle-east-23792641A/playlist.sxml
Error code : CDNRedundancyManagerError [0] : 

null

This appears to be a Flash file attempting to play.

Joe

Problem solved! I downloaded and installed Firefox 24.0 Beta. Apparently Mozilla programming team made all the right changes in the new release. Now all videos starting working on Yahoo and BBC.

Link: http://www.mozilla.org/en-US/firefox/channel/#beta

My Firefox stopped playing u-tube and Yahoo videos a little over a week ago. All I got was a message "An error has occurred, please try again later. Learn More" I have tried most of the suggestions from the u-tube and Yahoo web sites. My Flash Player and Java are up to date as is my copy of Firefox. I even tried the Firefox Beta. Nothing worked, plus I downloaded a few problem programs in the process.. I am now going to uninstall the Firefox Beta and am going back to IE which works well. I will be monitoring this thread in case some Firefox change solves the problem. Good luck.

Hi clarew55, the Yahoo issue was a particularly persistent problem that resisted the tips that usually worked for Youtube.

This is some standard guidance that addresses the most common reasons for Flash problems in Firefox. I'm sure you've seen some of it before, but just in case:

(1) Make sure all recorders/downloaders that interact with Flash media are as up-to-date as possible, or disable them. (Your recorders/downloaders may appear on the Plugins or Extensions list, or both, on the Firefox add-ons page.)

(2) Disable hardware graphics acceleration in Firefox and in Flash

(A) In Firefox, un-check the box here and restart:

orange Firefox button (or Tools menu) > Options > Advanced > General > "Use hardware acceleration when available"

(B) In Flash, see this support article from Adobe: http://helpx.adobe.com/flash-player/kb/video-playback-issues.html#main_Solve_video_playback_issues

(3) Disable protected mode (Windows Vista / 7 / 8)

See this support article from Adobe under the heading "Last Resort": Adobe Forums: How do I troubleshoot Flash Player's protected mode for Firefox?