Yes, the HTML5 trial must have a few bugs in it still. Thanks for letting us know.

Mine don't mention HTML5 trial,this problem is getting old now they need to fix this already.

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

• Tools > Options > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove Cookies" from sites causing problems:

• Tools > Options > Privacy > Cookies: "Show Cookies"

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance/Themes).

• Don't make any changes on the Safe mode start window.
• https://support.mozilla.org/kb/Safe+Mode

Tried what you said to do but nothing worked :(

Which version of the Flash player do you have?

• http://www.adobe.com/software/flash/about/
• http://helpx.adobe.com/flash-player.html

to fix this flash player problem i went to adobe site and downloaded flashplayer_11_plugin_debug.ran this and it works for youtube

video playback errors. hope this helps.i also tried everyones ideas but only this worked for me

I have 11.3 and nothing works.

If you can't get Flash 11.3 to work then you can try to revert to Flash 11.2.

You can download the Flash 11.2 player via this direct link:

• http://fpdownload.macromedia.com/pub/flashplayer/current/licensing/win/install_flash_player_11_plugin_32bit.exe
• http://forums.adobe.com/thread/1022066

You (may) need to uninstall the Flash 11.3 version if you downgrade Flash.

• http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html

I had the same problem. Came back from vacation on 6/21 and found updates for flash and firefox waiting for me. I updated. New updates of flash and firefox not compatible and while some things I wanted to do were available, many others such as games and listening to conferences were not. I used system restore to go back to a date before I went on vacation and everything works fine, just like before. My about firefox says I have an up to date firefox13.0.1 with yahoo edition 1.9 and my flash player says I am running 11.3.300.257. Apparently they are compatible for my HP DV7 with windows XP. I understand the updates are both for security issues and new features, but I have all the features I need, and I hope I have no security issues with my fix, but if you can't use the computer, what good is it that it is secure. It is secure if you turn it off also. I think those are pretty up to date versions, and why they work now, and why I had to do system restore are beyond my abilities, bu that is what worked for me,. To do system restore: go to start menu type in system restore in search box. Click on it and follow directions, set restore date to before problem started and when system was working.

This worked but when I go to other sites they ask me to upgrade

I have not had any sites asking me to upgrade. Can't help you, problem seems to be site specific..

THANK YOU...it was that damn HTML5 trial...