Your current list of extensions (from the "More system details" list), doesn't show any downloader extension installed.

In any case, here is the webpage you should visit to install the extension and to find answers to questions on using it:

https://addons.mozilla.org/firefox/addon/1-click-youtube-video-download/

The home page link for this extension link on the above page is broken. It's http://www.clickvideodownload.com/

Thank you for your reply, however the reason the list of extensions listed previously did not include 1-click YouTube Downloader as I had uninstalled it (several times) and unfortunately did not reinstall it until after I had added the question. My apologies. It is installed now, but I do not know how to include the current list of extensions installed in this section. I was prompted originally so it was easy then. Any clues please would be useful.

The issue however, is still unsolved. I suspect a file has become confused because of the many attempts at trying to find one downloader that worked, but although they did originally, none of them work now. Any assistance would be gratefully received.

You wrote, I do not know how to include the current list of extensions installed in this section. You can go to the Firefox Help submenu and open the "Troubleshooting Information" page, then click the "Copy text to clipboard" button and paste the information here. It will include a list of installed extensions. See the Use the Troubleshooting Information page to help fix Firefox issues article for details.

If your extension is installed and enabled but a button needed for the extension to work is missing, see if you can add the button to Firefox using the "Customize Toolbar" window:

1. Right-click an empty section of the Tab Strip
2. Select Customize.... The Customize Toolbar window opens.
3. Look for the missing button for your extension
4. Drag it onto the toolbar where you want it to appear.

The Customize Firefox controls, buttons and toolbars article has details. If that doesn't work (if there is no button for your extension) then I would post a comment at https://addons.mozilla.org/firefox/addon/1-click-youtube-video-download/ or else notify the extension developer. There's a "contact" link on the extension homepage, http://www.clickvideodownload.com/

Information from my Firefox installation is now pasted below, as per your instructions.

As far as dragging the button to the toolbar using Customise, it doesn't show in there (I have looked), but it would normally appear within the YouTube video page.

The images attached show a YouTube page with the button missing and another of when it worked previously.

Application Basics

Name: Firefox Version: 26.0 User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:26.0) Gecko/20100101 Firefox/26.0

Extensions

Name: 1-Click YouTube Video Downloader Version: 2.2.4 Enabled: true ID: YoutubeDownloader@PeterOlayev.com

Name: Adblock Plus Version: 2.4.1 Enabled: true ID: {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}

Name: Adblock Plus Pop-up Addon Version: 0.9.1 Enabled: true ID: adblockpopups@jessehakanen.net

Name: Add to Amazon Wish List Button Version: 1.10 Enabled: true ID: amznUWL2@amazon.com

Name: Pocket Version: 3.0.4 Enabled: true ID: isreaditlater@ideashower.com

Name: Save as PDF Version: 1.5 Enabled: true ID: save-as-pdf-ff@pdfcrowd.com

Important Modified Preferences

browser.cache.disk.capacity: 358400 browser.cache.disk.smart_size.first_run: false browser.cache.disk.smart_size.use_old_max: false browser.cache.disk.smart_size_cached_value: 358400 browser.newtab.url: about:home browser.places.smartBookmarksVersion: 4 browser.sessionstore.upgradeBackup.latestBuildID: 20131205075310 browser.startup.homepage_override.buildID: 20131205075310 browser.startup.homepage_override.mstone: 26.0 dom.mozApps.used: true extensions.lastAppVersion: 26.0 font.name.serif.x-western: Arial gfx.direct3d.last_used_feature_level_idx: 0 network.cookie.prefsMigrated: true places.database.lastMaintenance: 1390213375 places.history.expiration.transient_current_max_pages: 104858 plugin.disable_full_page_plugin_for_types: application/pdf plugin.importedState: true privacy.cpd.cookies: false privacy.cpd.downloads: false privacy.cpd.formdata: false privacy.cpd.history: false privacy.cpd.sessions: false privacy.sanitize.migrateFx3Prefs: true storage.vacuum.last.index: 1 storage.vacuum.last.places.sqlite: 1389980717

Graphics

Adapter Description: Intel(R) HD Graphics 3000 Adapter Drivers: igdumd64 igd10umd64 igd10umd64 igdumd32 igd10umd32 igd10umd32 Adapter RAM: Unknown Device ID: 0x0116 Direct2D Enabled: true DirectWrite Enabled: true (6.2.9200.16571) Driver Date: 10-31-2013 Driver Version: 9.17.10.3347 GPU #2 Active: false GPU Accelerated Windows: 1/1 Direct3D 10 Vendor ID: 0x8086 WebGL Renderer: Google Inc. -- ANGLE (Intel(R) HD Graphics 3000 Direct3D9Ex vs_3_0 ps_3_0) windowLayerManagerRemote: false AzureCanvasBackend: direct2d AzureContentBackend: direct2d AzureFallbackCanvasBackend: cairo AzureSkiaAccelerated: 0

JavaScript

Incremental GC: true

Accessibility

Activated: false Prevent Accessibility: 0

Library Versions

NSPR Expected minimum version: 4.10.2 Version in use: 4.10.2

NSS Expected minimum version: 3.15.3.1 Basic ECC Version in use: 3.15.3.1 Basic ECC

NSSSMIME Expected minimum version: 3.15.3.1 Basic ECC Version in use: 3.15.3.1 Basic ECC

NSSSSL Expected minimum version: 3.15.3.1 Basic ECC Version in use: 3.15.3.1 Basic ECC

NSSUTIL Expected minimum version: 3.15.3.1 Version in use: 3.15.3.1

Copied from the troubleshooting info you posted:

Extensions
Name 	Version 	Enabled 	ID

1-Click YouTube Video Downloader	2.2.4	true	 YoutubeDownloader@PeterOlayev.com

Adblock Plus	2.4.1	true	{d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d} 

Adblock Plus Pop-up Addon	0.9.1	true	adblockpopups@jessehakanen.net

Add to Amazon Wish List Button	1.10	true	amznUWL2@amazon.com

Pocket	3.0.4	true	isreaditlater@ideashower.com

Save as PDF	1.5	true	save-as-pdf-ff@pdfcrowd.com

I see that you have the latest version (2.2.4) of the 1-Click YouTube Video Downloader extension and it's enabled. So, if there is no "Download" button for your extension when you are on a page with a video, and there is no button you can add from the "Customize Toolbar" Firefox window:

I would post a comment at https://addons.mozilla.org/firefox/addon/1-click-youtube-video-download/ or else notify the extension developer. There's a "contact" link on the extension homepage, http://www.clickvideodownload.com/

P.S. Something else you could try first, in case one of your other extensions is interfering:

Go to the Firefox menu, click on Add-ons and then, in the list of Extensions, disable all of your other extensions and just leave the 1-Click YouTube Video Downloader enabled. Then restart Firefox.

Thank you for both your messages. I did Disable all other Extensions and restart Firefox, but unfortunately this made no difference, even though it did work originally. I have, as suggested, sent an email to the developer and if I do receive a response from them, I will post it to this question.

I have now resorted to finding an extension that does work and although I did this exercise the other day without success, I have now installed "Easy YouTube Video Downloader Express 7.20", which does show a more subtle Download button in Green but in a slightly different place on the YouTube Video page, so instead of to the right of Subscribe button, it is underneath.

How do you wish me to proceed with this message stream as although your suggestions didn't work, the issue has now been resolved by using a different extension, bearing in mind that any response I receive from 1-click YouTube Download developer would be best posted here?

PS - Having now done a little research, it would appear that YouTube has recently made some changes to prevent professional concert videos being downloaded. This has apparently caused many video downloader add-ons to fail. The developers of Easy YouTube Video Downloader Express 7.20 state in the text of their extension that they have managed to overcome the problems caused by YouTube's changes in this version. All I can say is that this 7.20 version does work!

Hi, Jenny,

Thanks for posting back with the outcome. Since you resolved the problem by installing a different extension, there's really nothing left to do here. This question is already marked "solved".

If you need help in the future, please ask a new question.