First, update your Shockwave Flash.http://get.adobe.com/shockwave/

I don't have Flash installed - it's blocked at my office.

OMG...

for it u have keep all your Shockwave updated

Thank You

and another thing is that dont open many tabs together

First, a technical point: Safe Mode disables extensions, but it does not disable plugins. The "Never Activate" should indeed disable them.

Is the message you get from Windows or the Mozilla Crash Reporter? If it's the Mozilla Crash Reporter, you may be able to extract some information logged by Firefox about the problem. Please check the last section of the support article "Firefox Crashes" for steps to get the crash report IDs for reports you have submitted to Mozilla, and then post some of the recent ones here.

Either way, it's puzzling that Firefox would be starting up plugin-container.exe if all the plugins are set to Never Activate. Especially in Firefox's Safe Mode where we can't point the finger at an extension using a plugin. Hmm...

Is it possible that an external process, such as a security-related process, could be killing plugin-container.exe?

Re: technical point - got it. Thanks.

The error is from Windows. I tried to upload a screenshot in the original post, but it kept failing. It's working right now for whatever reason.

I don't have any information connected to crash reports because Firefox itself isn't crashing - just the Plugin Container. Even when I click "Close the program" on the error message, nothing happens, so I assume it's closing the plugin container program itself (as oppose to Firefox). The popup error window closes, and then reappears a short while later.

I suppose an external security process could be doing something, but I've been using Firefox for years without this popup.

The two troubleshooting articles recommended are below:

• Firefox uses too much memory or CPU resources - How to fix
• Firefox uses too much memory or CPU resources - How to fix

Thanks for the help, but I don't think this solves the problem.

I'm still experiencing the error even when in Safe Mode. I'll still experiencing the error when all plugins are set to "never activate". So, I don't think Firefox is using too may CPU resources or too much memory if Safe Mode and "never activate" are set, right?

In case plugin-container.exe has gotten damaged somehow, or there is some other problem in your Firefox program folder, could you do this:

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean. As described below, this process does not disturb your existing settings. Do NOT uninstall Firefox, that's not needed.

(1) Download a fresh installer for Firefox 37.0.1 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

(2) Exit out of Firefox (if applicable).

(3) Rename the program folder

(32-bit Windows folder names)

C:\Program Files\Mozilla Firefox

to

C:\Program Files\OldFirefox

(64-bit Windows folder names)

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

(4) Run the installer you downloaded in #1. It should automatically connect to your existing settings.

Any improvement?

Note: Some plugins may exist only in that OldFirefox folder. If something essential is missing, look in these folders:

• \OldFirefox\Plugins
• \OldFirefox\browser\plugins

Thank you, as well, for the help.

Sadly, the clean reinstall did not work. I am still receiving the error.

Any other suggestions?

You could try using Firefox ESR (Extended Support Release), which is made to be more reliable than the "normal" Firefox releases. Firefox ESR only gets new features every 8 versions, so it may not have some of the newer features that the "normal" release has. But what it does have is stability.

First, download the installer here: https://www.mozilla.org/en-US/firefox/organizations/all/

Next, uninstall Firefox and install Firefox ESR.

Let us know if this fixes the issue.

Thanks!

I haven't come up with many leads searching around, but by any chance do you use avast! 2015? https://forum.avast.com/index.php?topic=168376.msg1201169#msg1201169 - The only solution seems to be to turn off "Scan for browser add-ons" under Smart Scan.