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Why isn't Downloadhelper working with Youtube?


I have been using the Downloadhelper add-on for years on my laptop with no problem. I noticed about three days ago it was no longer working with any Youtube videos. The rotating icon is still working, and when I click on it, it still gives me the file type choices for downloading. However, after I click my choice, the green arrow shows the downloading process, but comes up '0 bytes' for every type of video.

I am not having problems downloading videos from other sites that I've used before, just Youtube.

Also, I am able to use Downloadhelper with Youtube on my other computer without a problem.

Can you please help? Thanks.

Chosen solution

Google/Youtube are trying to block addons like these, maybe its been blocked from youtube, i would try FVD. https://addons.mozilla.org/en-us/firefox/addon/flash-video-downloader-youtube/

Read this answer in context 7

Additional System Details

Installed Plug-ins

  • Next Generation Java Plug-in 10.21.2 for Mozilla browsers
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Shockwave Flash 11.7 r700
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • Adobe PDF Plug-In For Firefox and Netscape 11.0.03
  • Google Update
  • GEPlugin
  • 5.1.20125.0


  • Firefox 21.0
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  • Advanced SystemCare Surfing Protection 1.0 (ascsurfingprotection@iobit.com)
  • DownloadHelper 4.9.15 ({b9db16a4-6edc-47ec-a1f4-b86292ed211d})
  • Troubleshooter 1.1a (troubleshooter@mozilla.org)
  • Easy YouTube Video Downloader 6.8 ({c0c9a2c7-2e5c-4447-bc53-97718bc91e1b}) (Inactive)
  • HP Smart Web Printing 4.51 (smartwebprinting@hp.com) (Inactive)


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Modified Preferences

  • accessibility.typeaheadfind: True
  • accessibility.typeaheadfind.flashBar: 0
  • browser.cache.disk.capacity: 358400
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  • User JS: Yes
  • Accessibility: No
  • Top 10 Contributor
  • Moderator
10744 solutions 96672 answers

Note that there is also a 4.9.18a1 version that addresses further issues.

_mig 1 solutions 13 answers

This version http://www.downloadhelper.net/install-beta.php?version=4.9.18a3 fixes the YouTube issues. You can install it right now or wait a couple of days for the official update.

maynard1857 0 solutions 1 answers

It seems the fix is that if you choose MP4 the clip will not download properly.......I chose to download as a FLV and I had no problems with the downloaded file

validated 1 solutions 40 answers

downhelper 4.9.21 FF v23.0.1 it's (hit and/or miss) sometimes it say 0 bytes sometimes it downloads but i CAN'T move it out from browser download area. It is suppose to go to dwhelper directory but It does not Usually I just pull it out of the browser downloads area.


validated 1 solutions 40 answers

I cheated, I downloaded with Real Player but that was only once. I can't repeat it.

TheOldFox 110 solutions 619 answers


  1. Read the following comment in the VDH bug report 536 and follow the instructions there (re: reload page several times, wait until after any ad plays, etc.).
  2. With Youtube changing the signature on files on a regular basis in an attempt to keep users from downloading videos, VDH has to try to guess the signature being used by Youtube.
  3. If you continue experiencing problems, post in the that VDH bug 536 thread will as much detail and links as possible and maybe they can help you find a solution.

VDH bug 536 - http://bugzilla.downloadhelper.net:8080/show_bug.cgi?id=536#c262

validated 1 solutions 40 answers

My video downloads were downloading to desktop then

they would vanish when they were done downloading.

I found work around that was to start playing it before it finished downloading. If I was to downloaded software I would lose it because there is no way to execute before it's done downloading.

And that will not work the next I do that.


  • Top 10 Contributor
  • Moderator
10744 solutions 96672 answers

If files are downloaded (you see a progression bar and file size not zero), but disappear after the download has finished then there is almost always security (anti-virus) software involved that removes the file or otherwise interferes.

Question owner

UPDATE: Today I randomly tried Downloadhelper and it is now working!! I did not apply any kind of changes, so whatever bugs they had are now fixed... for me anyway. (I had originally thought my IP address had been blocked.) Thanks to everyone for your suggestions, they will surely help someone else with similar issues.

As a backup, I installed another add-on, 'YouTube Video, Audio, and Subtitle Downloader' This works great as an alternative.

validated 1 solutions 40 answers

I ended up reloading an Image backup that fixed some problems.

emzeau 0 solutions 1 answers

Kdog's response fixed my problem, Thank you!!

Rochable 0 solutions 5 answers

Was somewhere else

Modified by Rochable

Rochable 0 solutions 5 answers

I tried your link changing from 4.9.21 to 4.9.18a3 (without any other Downloader), still sticking on first video opened.

Rochable 0 solutions 5 answers

I can always (and only) download the files from the first video played on the page.

validated 1 solutions 40 answers

I have FF 24.0 & downloaderHelper 4.9.21 No problems


Dyvik Chenna 7 solutions 96 answers

uninstall all the addons and restart Firefox.

Rochable 0 solutions 5 answers

I have tried resetting Firefox ( Firefox menu : ? \ Troubleshooting Information \ Reset Firefox), and reinstall Videos Downloaders (they all have the same behaviour), it did not solve the problem.

My problem : On YouTube, when more than one video have been played, staying on the same page, videos aivalable for download, by any Firefox Download Extension as Downloader Helper, Flash Video Downloader or 1 Click Video Download, are the format options for the first video opened in the tab, and not format options for the video actually playing.

Modified by Rochable

  • Top 10 Contributor
  • Moderator
10744 solutions 96672 answers

Maybe try to modify dwhelper expiration pref(s) on the about:config page.

  • dwhelper.menu-expiration
validated 1 solutions 40 answers

My downloadhelper 4.9.21 on FF 24.0 was working without problems. Yesterday, it stopped again. What I had to do was to download to desktop and play it before It finishes the downloading.

Bingo! No problem unless the clip is to short and you don't enough time to start playback.

Although, it would be if it just worked.


Rochable 0 solutions 5 answers

Hi Cor-El. About Dwhelper expiration pref(s) on the about:config page, dwhelper.menu-expiration :

The value you refer to is set in : DownloaderHelper / Preferences / General / Behavior / Menu entry expiration (sec) : 60 as set by default. I do not know what behaviour it changes, but it does not affect the sticking on the first video played on the page problem I have, which is the same for any downloader (Downloader Helper, Flash Video Downloader or 1 Click Video Download) I tried on Firefox.

Hi Validated. About « Yesterday, it stopped again. What I had to do was to download to desktop and play it before It finishes the downloading.» It Seems you have something that automatically erase the video you download ?

Modified by Rochable