Hello fairylight,

I went to add-ons and typed in download helper in the search box. The first item on the list is Video Download Helper 4.9.15 is this the add-on you are having a problem with?  If so I want to recommend a different add-on I have used very successfully - in add-on search type in Flash Video Downloader.

Flash Video Downloader 3.9.3 should appear. It adds a small arrow next to the location bar, when playing a video you can download it turns blue. click on the blue arrow, sometimes several download items appear, you almost always want the largest one in MB, click download. A save media file opens, you can change the title if you want, I usually add a numeric prefix to organize things for burning. click save - reduce download items box to an icon. Video download helper is very fast always finishing before the video finishes playing. check the progress of down load by clicking on arrow to the right of google search box. let me know if this helps you. David241

Yes it is ok to ignore the message if you trust the add-on. The message is just to warn you that add-ons are not developed y Mozilla and there is a risk to using them. If you trust the add-on(s) feel free to install

I'm attaching a screen shot of the standard dialog. If you see a different dialog, it might be a warning from Windows or your security software. In that case, it would be worth taking a closer look.

You can set an exception for the addons.mozilla.org site to prevent this warning.

• Tools > Page Info > Permissions > Install Extensions and Themes
• Tools > Options > Security : "Warn me when sites try to install add-ons": Exceptions

Thanks guys, all the answers were useful :D

I glad you found a solution. I should have told you I tried video download helper4.9.15 and found it difficult to use, probably it is just me. I found flash video downloader 3.9.3 much easier to use. For music downloads you might like to try MP4 you tube downloader 1.3.2.2 to remove any add-on you no longer want click add-ons then click extensions then select the item and click remove. Add-ons are easy come easy go, I like that.