A word of warning about using clipconverter and similar services,
Be aware of what you're clicking. Even though the service itself may be legitimate, it makes money by selling ads, which in and of itself might carry spam or viruses.
These ads may try to get you to click on them, or mimic part of the function like say "download" to make you click on it, instead of the actual download button.
Also, I've used it a couple times and a window pops up selling something. Caution needs to be dealt w/ these types of pages too, as some may not want you to close the page and ask you are you sure? making you click a page that downloads a virus or redirects you to a harmful web site.
When a window won't let you close, 'usually' you can close it by clicking the red X at the top right corner. Sometimes that doesn't work and something pops up that says 'are you sure" or something similar, again, possibly to get you to click on it. It is also a legitimate process too, but to make certain you don't click on something malicious in your browser window, Press "Control" + "Alt" + "Delete" simultaneously to bring up the task manager. Chose the browser under "Applications", then click "End Task"
My computer won't let me download the latest version of YouTube Downloader, I use it to also convert files as well as download videos. It may be because YTDownloader 'tries' to get you to use "Yahoo's Toolbar" and other applications (how it gets paid) and those are sometimes connected to virus or spam files.
Usually you can opt out of installing those by unchecking and 'declining', (YouTube Download would then install w/o the add ons), so you can use the program. It's the Yahoo add ons and tool bar which I think Norton's recognizes as Spam or Virus activity, and why it blocks then deletes YT Downloader when I try to download it.
It's also possible it's being blocked because it's 'new' version and not yet recognized.
As of now, I can't find a 'safe' way to download YouTubes, most free programs that do this are suspect anyway, so it's treacherous path.
YTDownloader used to be a safe and effective program, unfortunately, until they figure out what the issue is, BE CAREFUL using whatever alternative you find
(My laptop uses Microsoft Security Essential, which allowed YTD to download, but once installed, it still doesn't work... so that's a bummer
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(BTW, I did get a virus, it snuck into my back up hard drive and messed up Norton's for a few hours, wouldn't scan my hard drive, so I had to get help from Norton's to remove it and make certain Norton's worked again and my computer was virus free
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Not sure I got it from using clipconverter or when I was searching and downloading YTD alternatives sooo.... again, proceed with caution
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Hope they fix it soon because I use it alot to make my videos