Can you post a link to a not working video?

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

• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

I started in safe mode The problem still occurs in Safe Mode

   I Turned off hardware acceleration

problem persists

   I Switched to the default theme

problem persists

  I Disabled all extensions

problem persists

vimeo.com homepage has a video that will not play as an example.

I have no idea whats going on, I reinstalled 10.2 FF and no change, this is not an issue with a plugin as far as I can tell.. IE plays videos just fine, please dont tell me I have to switch to IE I would sooner hang myself.. thankful to anyone who can solve this!

No problems here with the videos on the Vimeo site.

Those videos are mp4 files played by a Flash player: http://av.vimeo.com/23687/108/86752410.mp4

Do you see the Vimeo Flash player and controls?

If I right click on the video I see settings and global settings, I can choose global settings and see all the options, but interestingly,when I choose "settings" nothing happens.. I assume a new menu is supposed to appear, something? Thanks for the reply.. still in the weeds with this though.

This is all I see on Vimeo, I can click where the video is supposed to be and get some settings menus, but as I said above, when I click on "settings" nothing happens. I can choose global settings but all that comes up is a bunch of settings regarding camera and peer assisted stuff I really don't understand.

Make sure that you allow the plugin-container process in the firewall.

See also:

• http://kb.mozillazine.org/Plugin-container_and_out-of-process_plugins

OK I read the link you posted and I tried changing dom.ipc.plugins.enabled;true and dom.ipc.plugins.java.enabled;true to false, and back to true again. Nothing changed and I could not really understand the majority of the thread you posted, I am not a coder and I have no idea what any of that stuff even is.

I don't know how to "allow the plugin container process in the firewall" I googled it but all I find is more cryptic forum threads and I have no idea what any of it means.

Am I supposed to be looking at settings in my commodo program?

I am doing my best here, and trying to solve the issue, I really appreciate all your help. It is very frustrating because I am not familiar with browser settings and technical things relating to plugin containers and out of process plugins.

Thanks again for all your help, but nothing seems to be working.

OK... Now it works, starting today for no reason that I can see. So strange.. nothing worked and all of a sudden it is playing videos fine. I did nothing different, I did not update FF.. Makes me think it was something with my PC now.. ASUS gaming laptop. No idea why it works, I wish I could tell you how I fixed it but I honestly don't know. Sorry I guess this thread is worthless but I still wanted to update it and say thanks for all the help.