Could you visit the following test page and after it detects your plugins, search in the page for SiteAdvisor? I suggest that because it might be under a name other than McAfee, making it hard to find on the Plugins page.

https://jeffersonscher.com/res/jstest.php

Occasionally Firefox's plugin registration file may become corrupted and need to be regenerated. Basically, you delete it and Firefox will re-scan the registry and relevant folders to find your plugins. Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using

Help > Troubleshooting Information > "Show Folder" button

Leaving that window open, switch back to Firefox and Exit

Pause while Firefox finishes its cleanup, then rename pluginreg.dat to something like pluginreg.bad

Restart Firefox. Hopefully that error will be gone.

Any luck?

Hmm, when you say you did a fresh install without the extensions, did you remove your personal data (or create a new profile) so that you would already have generated a fresh pluginreg.dat? In that case, Firefox may still be finding SiteAdvisor in the Windows registry.

If you are comfortable using regedit.exe, look in these keys for a SiteAdvisor entry (not all key will necessarily exist):

• HKEY_CURRENT_USER\Software\MozillaPlugins
• HKEY_CURRENT_USER\Software\Wow6432Node\MozillaPlugins
• HKEY_LOCAL_MACHINE\SOFTWARE\MozillaPlugins
• HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\MozillaPlugins

Note that your attached System Details List is showing the SiteAdvisor under the Plugins heading.

You can find the installation path of all plugins on the about:plugins page.

• http://kb.mozillazine.org/Issues_related_to_plugins#Identifying_installed_plugins

OK, Here is the deal: This is a Domain laptop. I cannot log in to just hardware as a result. I know beyond the shadow of a doubt that the McAfee site advisor is locking up both Firefox and IE9, IE10, and IE11. MY question is how can I manually edit something specifically in Firefox to ensure the plug in will NOT under ay case . I am not abel to remove it form the system registry. It just keeps replacing itself. I cannot uninstall it due to Admin control beyond my level. Google Chrome ignores the errors and bypasses the plugin automatically. IE just plain becomes useless. Firefox continuously pops up Siteadvisory plugin error and asks to stop it. Upon a complete removal of FireFox and reinstall with all FF related Registry entries deleted and all folders deleted, when it re installs, McAfee shows back up again and the problem starts all over. There is one catch... After a fresh boot up, the first instance of Firefox (or IE for that matter) it will run. Any new tab or new window after the first instance from that point on, crash and burn..... So basically, I am suck unless there is a means to force that plugin to not run no matter what. How can I do that?

If you cannot set the plugin to "Never Activate" on the Add-ons page (obviously simplest), you may be able to do it via a preference in about:config.

Did you find SiteAdvisor on the about:plugins page or in pluginreg.dat? What is the name of the DLL file?

In about:config, search using the following pattern:

plugin.state.

If you have any deactivated plugins, you'll see a pattern which (with the exception of Flash and Java) seems to have some or all of the DLL file name. For example, I have these deactivated plugins:

• ActiveTouch General Plugin Container, npatgpc.dll
  plugin.state.npatgpc=0 (exact match to DLL name)

• Google Talk Plugin, npgoogletalk.dll
  plugin.state.npgoogletalk=0 (exact match to DLL name)

• Google Update, npGoogleUpdate3.dll
  plugin.state.npgoogleupdate=0 (truncated before 3)

• Shockwave for Director, np32dsw_1202122.dll
  plugin.state.np32dsw=0 (truncated before _)

Without reading up on it, I can't be sure of the pattern here, but maybe it will be simple in this case?