Could you check your actual Firefox version, because the version reported by the forum software doesn't make any sense.

Help > About Firefox

You might also refer to this article: How to reset the default user agent on Firefox.

The version of firefox i am using is 3.0.19

Why? That version is more than 3 years old and I'm sure has a lot of security issues. Can't you upgrade?

By the way, in order to avoid losing bookmarks if you leap to a current version, please make a backup from the Bookmarks Manager to a location outside the Mozilla\Firefox folder, such as the desktop or your documents.

I have updated fire fox and flash to the most latest version, but the youtube videos still have blank thumbnails, I have attached image of youtube.

Here are some suggestions. You probably tried some, but I'll include as much as possible.

(A) Site-specific image block

Could you make sure you aren't blocking images from ytimg.com? You can check for that here:

orange Firefox button (or Tools menu) > Options > Content

Click the second "Exceptions" button (the one to the right of "Load images automatically").

(B) Cache / cookie inconsistency

When you have a problem with one particular site, a good "first thing to try" is clearing your Firefox cache and deleting your saved cookies for the site.

(1) Bypass Firefox's Cache

Use Ctrl+Shift+r to reload the page fresh from the server.

Alternately, you also can clear Firefox's cache completely using:

orange Firefox button (or Tools menu) > Options > Advanced

On the Network mini-tab > Cached Web Content : "Clear Now"

If you have a large hard drive, this might take a few minutes.

(2) Remove the site's cookies (save any pending work first). While viewing a page on the site:

• right-click and choose View Page Info > Security > "View Cookies"
• Alt+t (open the classic Tools menu) > Page Info > Security > "View Cookies"

Then try reloading the page. Does that help?

(C) Userscripts

I noticed you have Greasemonkey. Could you disable it temporarily and reload the page to see whether any of your scripts are affecting it? Either click the monkey icon (it should become faded) or use Tools menu > Greasemonkey > Enabled (to toggle it off). You can re-enable GM the same way.

(D) Extensions

Next would be to try Firefox's Safe Mode, a standard diagnostic tool to bypass interference by extensions (and some custom settings). More info: Diagnose Firefox issues using Troubleshoot Mode.

You can restart Firefox in Safe Mode using

Help > Restart with Add-ons Disabled

In the dialog, click "Start in Safe Mode" (not Reset)

Safe mode does not automatically disable plugins. If you want to rule those out as well (except Shockwave Flash, of course), you can disable them here:

orange Firefox button (or Tools menu) > Add-ons > Plugins category

Any difference?

Hello,

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

Thank you.

Hi Jscher200 I tried everything you requested, but did not solve the problem

Tylerdowner - Did the reset firefox feature and it worked. Thanks guys problem solved.

Since upgrading firefox and flash I am now getting the "Unresponsive Plugin; Shockwave flash may be busy, or it may have stopped responding" on almost all websites, its driving me crazy, cannot watch any videos as it crashes.

Hi 2jan, what are your current Firefox and Flash versions?

• Firefox: Help > About Firefox
• Flash: orange Firefox button (or Tools menu) > Add-ons > Plugins (listed as Shockwave Flash)

Does that message appear in the rectangle where you would expect the video to play? Do you get the icon that looks like a piece of LEGO with a sad face?

Since your reset, have you installed any plugins or extensions related to video, such as downloaders or recorders? You can use the various categories of the add-ons tab to review what you may have acquired intentionally or unintentionally.