you have many custom network settings, this might be a problem - please go into about:config and reset all custom entries (the ones that are shown in bold) that start with network. or try to reset firefox altogether.

You can also check for problems caused by extensions.

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

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

• Do not click the Reset button on the Safe mode start window or otherwise make changes.

• https://support.mozilla.org/kb/Safe+Mode

Well, I've done all those things, even turned off my anti-malware and anti-virus software. I still can't load videos from YouTube nor click through email to view the videos. This is really frustrating, especially since my wife can't go there either, and she is set up a lot simpler than I am.

Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

If the new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See:

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

You can also try to reset Firefox:

• https://support.mozilla.org/kb/Basic+Troubleshooting