Rated 1 out of 5 stars

Wasted hours trying to get it to work with to no avail. Now I have to waste more time getting rid of it. Terribly complicated to use. I'm sorry I ever looked at it.

This review is for a previous version of the add-on (4.9.15.1-signed). 

Great extension... Rated 5 out of 5 stars

..Youtube is being an asshole though. Some videos can be downloaded, others can't. I don't envy the developer(s) of this extension trying to keep up with Youtube's BS.

This review is for a previous version of the add-on (4.9.15.1-signed). 

Please check the presumably fixed beta version from http://bugzilla.downloadhelper.net:8080/show_bug.cgi?id=536#c9

Stopped working Rated 3 out of 5 stars

It seems that the latest Youtube update has broken this fine addon. I hope the developer updates it soon! :'(

This review is for a previous version of the add-on (4.9.15.1-signed).  This user has a previous review of this add-on.

Rated 4 out of 5 stars

0 kb videos from latin america. Complet 0kb videos of channel Caribe Mix TV, or Musichitfactory. Please give us new version DownloadHelper

This review is for a previous version of the add-on (4.9.15.1-signed). 

Please check the presumably fixed beta version from http://bugzilla.downloadhelper.net:8080/show_bug.cgi?id=536#c9

0 bytes wtf Rated 3 out of 5 stars

Stupid Youtube's music video blocking script is still working! Please, please, please find a way to fix it!

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 4 out of 5 stars

Thanks for the addon, works wonderfully.

The icon's a bit ugly though, but utility-wise never had any problems.

This review is for a previous version of the add-on (4.9.15.1-signed). 

j adoooooooore Rated 5 out of 5 stars

=)

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

very handy and effective

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

As of June 20, 2013, the "0 bytes" problem still exists when trying to download YouTube videos.
Video DownloadHelper isn't the only add-on affected.
"Download Flash and Video" is also affected (in exactly the same manner), and "Flash Video Downloader" might be too.

This review is for a previous version of the add-on (4.9.15.1-signed).  This user has a previous review of this add-on.

Great Progam, as for 0kb FIX Rated 5 out of 5 stars

great progeam 5/5 have used for quite some time i can download videos from all sites , only problem i've had is clearing cache on site updates(to clear 0kb error) which is really minor and rarely happens.
For 0kb fix
https://support.mozilla.org/en-US/questions/936202
- TL;DR
Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

Tools > Options > Privacy > Cookies: "Show Cookies"

Try to delete the webappsstore.sqlite file in the Firefox Profile Folder to clear the current local storage aka 'super cookies'.

You can use this button to go to the Firefox profile folder:

Help > Troubleshooting Information > Profile Directory: Show Folder

This review is for a previous version of the add-on (4.9.15.1-signed). 

DownloadHelper 4.9.15 - 0kb Fixed :-) Rated 5 out of 5 stars

I had the "0kb error" too...
I tried these steps :
1) Uninstall DHelper 4.9.15
2) set user rights to administrator level (control panel/user accounts)
3) ReInstall Download Helper as usual
4) set user rights back to "user" level (control panel/user accounts).
Everything work now just fine for me.
(Win 7 x64 SP1 / Firefox 21.0 / Download Helper 4.9.15)
Unless there are other factors in your case...

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

Самое функциональное дополнение которое я видел вообще в браузерах для скачивания видео....

This review is for a previous version of the add-on (4.9.15.1-signed). 

Youtube issues... Rated 4 out of 5 stars

After the resolution of the previous round of issues (not able to comment, like, add to favourites/playlist etc.), it looks like Youtube has made further changes to their script to block downloading of videos?

Over the past few days, after downloading, the file name shows up in the list of downloads but with 0 KB and no file appears in the target directory...

This review is for a previous version of the add-on (4.9.15.1-signed).  This user has 2 previous reviews of this add-on.

Rated 5 out of 5 stars

Yes, my favorite Firefox add-on. But I've also experienced the 0kb downloads for some videos. LOEN Entertainment videos are another example of videos that don't download.

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

Love this app .. for users who don't have unlimited internet bandwidth ... we can download and play videos and works on almost all sites...

This review is for a previous version of the add-on (4.9.15.1-signed). 

Doesn't work with VEVO Rated 2 out of 5 stars

Today i tried to download videos from VEVO and it marks 0kb error.... Hope this will be fixed soon. version 4.9.15

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

I'm using Firefox 21 and it works perfectly with YouTube and other sites I use for watching videos.

This review is for a previous version of the add-on (4.9.15.1-signed). 

0kb bug with many videos Rated 5 out of 5 stars

Giving 5 stars to the app itself, but starting today I'm also getting the 0kb error for many youtube/VEVO videos. Fingers crossed this will be fixed soon.

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

best add-on ever...

This review is for a previous version of the add-on (4.9.15.1-signed). 

Rated 5 out of 5 stars

Doesnt works anymore with most latest YT Videos since today. Most Videos have 0 Kb tested in FF 15 and 21. I anyways give 5 Stars because it was working flawless before

This review is for a previous version of the add-on (4.9.15.1-signed).