VideoHelper logoMy favorite tool for downloading YouTube clips on Mac is the DownloadHelper extension for Firefox. It's convenient, quick and even converts videos into the format of your choice while it downloads. For a while however I've been plagued with a "Conversion requires external application" error message when downloading certain clips.

The exact error read: "Conversion requires an external application that appears to be missing on your system. Configure conversion? > Cancel > OK." When I selected OK, it opened the Preferences for DownloadHelper highlighting in red the location path for the selected converter option which is either FFMpeg or MEncoder.

I eventually found the start of the solution was to install the ffmpegX video/audio encoder for Mac. ffmpegX is basically a Mac OS X graphic user interface designed to operate more than 20 video and audio processing tools including ffmpeg which is a very fast video and audio encoder.

For the purposes of correcting the DownloadHelper error, you don't actually need to use the ffmpegX interface. You do however need it to use it to install the mpeg2enc binary for ffmpegX. Once you've installed ffmpegX, you'll be immediately taken to the main interface where you'll be prompted to load 3 binaries. You only need to load one binary to fix DownloadHelper - the mpeg2enc binary - which can be found here.


You don't have to worry about the mencoder or mplayer binaries but you do need to check the box next to mpeg2enc and locate the binaries that you've downloaded onto your hard drive. The resulting installation places the binaries in your Mac's application support library. The final step is to re-open your DownloadHelper preferences (in Firefox's Tools menu) and enter the path where the binaries are located. For most people, it will be "/Library/Application Support/ffmpegX":


When the DownloadHelper logo animates next to the URL bar while you are using YouTube, you should now be able to download videos again with it. However, it hasn't worked perfectly for me. For some reason, videos are being downloaded to a temporary file on my Mac rather than the directory I've configured downloaded files to be saved in DownloadHelper. In addition, the files are not being converted to QuickTime format they were previously. However, I can sort-out all of this by manually moving the files and converting them myself later. The important thing is that this work-around allows you to download YouTube clips again using DownloadHelper.


  • Steve Wood |
    Steve Wood

    Thanks for you great advice! I actually got it it work on my Mac!!

  • Nicholas Mead |
    Nicholas Mead

    Glad it helped Steve. It really had me stuck for a while too.

  • Windom Pearl |
    Windom Pearl

    Thanks very much! I finally got it all to work because of you. Perhaps you could add an extra bit explaining how to download a binary file (I had to work that out elsewhere). Cheers.

  • CB |

    Thanks! I couldn't figure out the correct path to type in! /Library/Application Support/ffmpegX Works like a charm.

  • OceanDeep |

    perfect thanks so much <3

  • Marcus Robb |
    Marcus Robb

    Thanks heaps.. the perfect solution to n awesome little ap!

  • David |

    Thanks for the fix. Only thing is I can't find the downloaded files. i see that they are downloading and cleary not to the path where I told them to (as you mentioned would happen) but when I search for them with spotlight I can't find them. Any clues as to where that temp folder would be?

  • Nicholas Mead |
    Nicholas Mead

    Hi David, On Macs, you're usually prompted where you want to save the file when you select download. In my case, I usually save them to a folder labeled "dwhelper" in my user folder.

  • Chris |

    I've downloaded an ran ffmpegX from my Applications folder. I've also downloaded the three binaries. Once I've located them and clicked install I get the following error message. Any suggestions? Thanks, Chris

    "The installation was not successful. WARNING: Improper use of the sudo command could lead to data loss or the deletion of important system files. Please double-check your typing when using sudo. Type "man sudo" for more information.

    To proceed, enter your password, or type Ctrl-C to abort.

    Password: Sorry, try again. Password: Sorry, try again. Password: Sorry, try again. sudo: 3 incorrect password attempts"

  • k |

    how do you download the binary file? All i see is a web page full of characters.

  • Darrell |

    Same thing here as "k" nothing but code. I'd really like to get this working

  • Ed |

    thanks - worked perfect!

  • Nicholas Mead |
    Nicholas Mead

    @K and Darrell - That code IS the binary file. Don't open it - just CMD-click or right-click and download it :)

  • Jessica |

    Hi, I was wondering if any one could help me figure this out. Whenever I try to download a video I keep getting a message that says:

    "Error Cannot create target file /Users/Njinsky/dwhelper/Brahms Violin Concerto-Vadim Gluzman(Part-2).flv. Please check available space and permissions."

    Download helper was working fine for a few years but it suddenly stopped a few months ago. I've looked all over on how to fix it and I can't find anything

  • Louise |


    Thanks for the instructions, but I'm really confused. I've downloaded the mencoder and mplayer because it said I needed them and then I read the bit in your post that says I don't need them. Presumably I can just trash these? The real problem though is that mpeg2enc. All the links I've tried just takes me to a page of symbols as one of the other guys above said. I've tried right clicking on the link but don't see anything that says I can just download it. Clicking on the link just takes me to the page of gobbledegook. Having used tubetv (which now seems to have gone down the tube), I've been trying for days to find something that will allow me to download youtube videos onto my ipod and now I just feel like crying. :(

  • Peter |

    Hey for the people having problems with the mpeg2enc download. What you need to do is hold down the alt button as you click the link. It should then ask you to save the page, just save it to your desktop. Then when the program asks you to locate it just click on the HTML page you just downloaded to the desktop and it should work.

  • steve |

    This fixed the problem i was having, the best way to find your downloaded files is from within firefox go to "tools" then "downloads" and then rightclick on the file and choose "show in finder". As it does put them in some weird temporary folder

  • Martin |

    So after obstacle and obstacle, I finally come towards the end of fixing this bug and then the most unexpected and petty obstacle comes up.

    I'm on what the author has called "the last step" and I am trying to get to the Download Helper preferences page. I go to Tools and then Download Helper but when I put my cursor over it, nothing happens. The arrow implying that there should be a sub-menu next to Download Helper is there, but when I scroll over it, no menu comes out! A) what should I do and B) is this the stupidest thing to get in the way of me fixing Download Helper?

  • Dodo |

    Thanks a million! I've been looking for the right pathway for SO LONG for this add on! Worked like a charm!

  • Bobbbi |

    I've followed all of the steps, but Download Helper still refuses to recognize the binary. What should I do? I saw that ffmpegx installed the binaries in hard drive's library so I copied it over to the usermame's library. However, it made no difference. I also tried VLC, but download helper refuses to recognize that as well.

  • Nicholas Mead |
    Nicholas Mead

    Hi Bobbi, The only thing I can suggest is to make sure that the path is correctly entered in preferences as "“/Library/Application Support/ffmpegX”.

    However, since this post was written, the application has been updated and you might be best just uninstalling and reinstalling it here:


  • Bobbbi |


    I tried everything you said and updated it. However, the only thing that seems to be different is that Download Helper will let me download things. Nonetheless, it retains the Adobe Flash format of the video. What can I do?

  • Nicholas Mead |
    Nicholas Mead

    Bobbi, Go into the "Tools" menu in Firefox and select "Add-Ons". Click on the preferences for DownloadHelper. Then select the "Conversion" tab and click the box "Conversion Enabled".

    One other thing, even if you don't do this, you should be getting an option to download files in MP4 format. When the DownloadHelper icon animates next to the URL bar, click the small black arrow next to it and you should get some choices of what format to download it in i.e.:

    Videoname.flv (HQ18) Videname.mp4

  • Chris |

    How do I uninstall the mpeg2enc binary from my mac system? I have no idea where to find it and it made my download helper problems worse. Downloadhelper now won't convert videos like I tell it to and it won't save them to the folder I tell it to no matter what I do, even after re-installing downloadhelper. I want mpeg2enc off my 'puter so can someone please tell me how to find it and get rid of it? Thx in advance, Chris

  • Nicholas Mead |
    Nicholas Mead

    Chris, I would think the way to do it is just uninstall ffmpegx (search for it using Spotlight) from your Mac. If that still doesn't work, check out the ffmpegx website:


  • Bart Brown |
    Bart Brown

    Can't get "Download Helper" to save video -- or anything else. I have read all the comments here, and at ffmpeg.org, ffmpegx.com, forumvideohelp.com, downloadhelper.net, aldorandenet.free.fr, www.apple.com/downloads/macosx/video/mplayerx.html, gst-ffmpeg.darwinports.com, www.macosxhints.com/article.php?story=20061220082125312 (An easy install of the ffmpeg command line tool - Mac OSX hints).

    I'll freely admit that I'm NOT familiar (or comfortable!) at all with messing about in the terminal with command-line stuff, but it seems to me there has to be a way to make Download Helper work on an Intel-core Snow Leopard Mac -- Snow Leopard has been around since August of 2009, and Intel Macs since LONG before that.

    Here are the particulars:

    System: iMac 27" 3.06 GHz Intel Core 2 Duo, 4 GB 1067 MHz RAM Mac OS X 10.6.3 Snow Leopard Mozilla Firefox v3.6.3 Download Helper v4.7.3

    The "Download Helper" "whirling balls" icon ONLY appears in the Firefox window (NEVER the toolbar) when I have a video (for example, a YouTube video) open. If I don't have a video open, the The "Download Helper" icon appears just to the left of the video's title,but it is NOT animated -- no "whirling balls". The icon has what would appear to be a "drop-down" menu triangle, but clicking on it results ONLY in the following message:


    When I click "OK", I get a preferences window with the tabs "General," "Capture," "Services," "Conversion," and "Miscellaneous."

    If I go to the "Conversion" tab, it says:

    "This feature lets you convert videos automatically as soon as they are downloaded," and the following boxes are checked:

    "Conversion enabled" "Notify conversion ending"

    the following box is NOT checked: "Share configurations"

    If I click on the "Configure conversion rules…" button, nothing happens.

    The last item in the window reads:

    "Converter," then a drop-down menu which offers me the choice of "FFMpeg," for which the entry box reads "/usr/bin/ffmpeg" IN RED, or

    "MEncoder," for which the entry box reads "/usr/bin/mencoder" IN RED

    This drop-down preferences box can NOT be closed, and the only way to get rid of it is to quite Firefox entirely.

    I have both the latest versions of both Movist (v0.6.8) and MPlayerX (v0.9.9 [r710]) installed. I also have FFusion v2.2 (build 72), although since there is no longer a /Library/QuickTime to put it in, it does me no good.

    Obviously I'm missing something here, apparently an FFMpeg application I'm unaware of. Can anyone help me with this?


    Bart Brown

  • Bart Brown |
    Bart Brown

    PS: I did EVERYTHING enumerated in "How to fix DownloadHelper conversion errors," including installing ffmpegX (v0.0.9x, two years old, but the latest I could find), and made sure the path in Download Helper's Prefs was correct. Same non-operation, same error message. What am I doing wrong?


  • J |

    Hi, I've done everything here and I don't think it is working. It downloads the *.flv file ok. And then, it doesn't matter if I choose the download and convert or convert manually, the queue progress just keeps saying "in progress".

    Any ideas?

    thanks, Joy

  • Tim |

    For why it's downloading to the Temporary Items folder, well, the name of the folder should explain it. Download Helper downloads the file that you selected to this folder, then re-uploads it to convert it. It then should download to the correct directory. As for if the conversion works or not is another thing entirely.

  • Tim |

    I was experimenting around with the binaries, and I got one to work: use mencoder binary and select MEncoder on the drop-down next to the binary locator. The conversion worked for me, and I tried it a few times, it should work.

  • Tim |

    Sorry, that format is only for Flash Video to QuickTime, which is won't play on any device. Use mpeg2enc, but still with MEncoder selected.

  • Emma |

    Okay, so I followed all these steps successfully, and then I realized that the "Download and Convert" option wouldn't work. You said that you could convert it outside of DownloadHelper, but I have no idea how, so I followed the link you gave in a comment about the 'updated' version, and downloaded THAT instead. This time, I don't have any error problems when I try to convert, but it just doesn't! It downloads perfectly, but it does not convert. How do I get the video into AVI format?

  • Emma |

    Oops never mind I just realized that the one you gave the link to was the same one I originally downloaded from the Firefox Add-on site (4.7.4.) But another thing I've realized is that, aside from not converting, even if I simply select "Download," it does not save on my Desktop like I want it to. So even if I magically found a free, safe program that could help me convert my .flv Youtube video into .avi, I wouldn't be able to because it doesn't even save, it just downloads! So frustrated. I just want to make a simple montage :'(

  • q |

    thanks for the advice!

    stumbled on an issue maybe someone could help me with?

    downloaded the mpeg 2 binary file fine but after locating it in ffmpegx and installing it, it cant be found in the application support? in fact there is no application support folder for ffmpeg in my library?

    - could this be an issue with where im downloading the binary file to? (currently just in a folder in docs) - could it be an update issue? - should i just create my own application support folder for ffmpegx?

    any help would be very much appreciated

    many thanks


  • riyas |


    I use ubuntu 10.4 and I had much trouble with converting youtube vedios to mp3. I have got latest ffmepgp installed onto my ubuntu pc. the only fix here is you have to change the path of ffmegp from /usr/bin/FFMpeg to /usr/local/bin/FFMpeg.

    If you have installed FFMpeg installed on your system and knows the path, substituting the path sould resolve the problem.as soon as the right path is entered the colour changed from red to blak.and is working for me now.

    I tried with Mencoder.blv me it works but was not good quality for me atleast

  • Ebonweaver |

    Actually there is a cleaner way to do this if you don't want to monkey with ffmpegx as an entire application. Once you download and mount the dmg, don't drag it to applications, right click and show package contents. Drill down to Contents/Resources and find ffmpeg. Copy that file to wherever you want, and then point the downloadhelper plugin to it's location. For example, I put it in /Users/myhome/bin so I typed in /Users/myhome/bin/ffmpeg. Works like a charm, and you can throw away ffmpegx at that point as you don't need it or the odd download things it needs to properly work. Why this pre-compiled ffmpeg binary in the ffmepgx application bundle isn't available as a download somewhere I can't figure out.

  • Nicholas Mead |
    Nicholas Mead

    @Ebonweaver, thanks for the shortcut tip. That should save a lot of users a lot of hassle judging by the popularity of this topic!

  • Gobe |

    having the same problem installing please help/suggest

    I’ve downloaded an ran ffmpegX from my Applications folder. I’ve also downloaded the three binaries. Once I’ve located them and clicked install I get the following error message. Any suggestions? Thanks, Chris

    “The installation was not successful. WARNING: Improper use of the sudo command could lead to data loss or the deletion of important system files. Please double-check your typing when using sudo. Type “man sudo” for more information.

    To proceed, enter your password, or type Ctrl-C to abort.

    Password: Sorry, try again. Password: Sorry, try again. Password: Sorry, try again. sudo: 3 incorrect password attempts”

  • Nicholas Mead |
    Nicholas Mead

    @Gobe, It sounds like you are entering the wrong password for OS X. You need to enter your system password for the command to execute properly.

  • Qosai |

    @Jessica If you did not get the following error fixed: Error Cannot create target file /Users/Njinsky/dwhelper/Brahms Violin Concerto-Vadim Gluzman(Part-2).flv. Please check available space and permissions.”

    Here is how to (using ubuntu linux): 1) launch your files manager using administrator permission (e.g sudo nautilus) 2) go to your home directory you will find the dwhelper folder. 3) change the permission of that folder from root to user (I mean your user name). that you worked with me ubuntu.

  • mig (DownloadHelper developer) |
    mig (DownloadHelper developer)

    The ffmpeg version that goes along with ffmpegX is outdated and cannot convert the newest youtube videos.

    You may want to use the ffmpeg file from package http://tools.rodrigopolo.com/bin/mac/binkit-v1.3.tar.gz and copy it to /usr/bin. Alternatively you can also install the package according to the instructions from http://rodrigopolo.com/about/wp-stream-video/ffmpeg-binary-installers-for-win-mac-and-linux#macosx

  • T |

    It looks like files are downloaded but I cannot find where I saved the files to. A few people seem to have same problem...any one solved this issue?

  • @T |

    Don't the files just come up in your download menu anyways? Just right click on one of the files saved using conversion and hit show in finder. Then make a note of where it is as all other files saved should likely go to the same folder.

    If it's really out of the way, you don't want to constantly have to navigate there and you can't to seem to change save location then you could create a shortcut to that folder from the desktop or any other preferable location or even drag the folder to the finder toolbar for super easy access.

  • As above |
    As above

    Oh and great article. The file location was really screwing with me, I kept sending it to /applications/ffmpgeX instead of to /Library/Application Support/ffmpegX

  • Lauren |

    Thank you so very much! I am very grateful for this tutorial. Even most video tutorials didn't make sense because they either didn't mention the steps to using the binary or they do something else that seems different from my comp. Thank you, again! <3

  • Boris |

    I had problems installing ffmpegX until I read on the download page: "Make sure that your startup disk has no spaces or special characters in its name." Sure enough the cute name I gave my startup disk did have a space in the name. Once I removed the space from the name and followed to the letter the installation instructions on http://ffmpegx.com/download.html I had no problem. Oh by the way to get the mpeg2enc binary I had to go to Safari because Firefox didn't have the option to "Download link on disk" when I did CTRL+click (but Safari did - go figure).

  • Bart Brown |
    Bart Brown

    Nicholas -- Followed your instructions this far:

    "For the purposes of correcting the DownloadHelper error, you don't actually need to use the ffmpegX interface. You do however need it to use it to install the mpeg2enc binary for ffmpegX. Once you've installed ffmpegX, you'll be immediately taken to the main interface where you'll be prompted to load 3 binaries. You only need to load one binary to fix DownloadHelper - the mpeg2enc binary - which can be found here," the 'here" being a link to http://mjpeg.sourceforge.net/MacOS/mpeg2enc.intel. But when I click the link all I get is several thousand lines of hash. This can't be right.

    Also, at the site you link to (ffmpegx.com) for DLing ffmpegx, the blurb says: "Download and install: Click to download and install the latest version of ffmpegX for MacOSX 10.2, 10.3 10.4 and 10.5."

    Nothing about 10.6 (Snow Leopard). I currently use OS X 10.6.6. Can I still use this version of ffmpegx?

    Thanks for your help!

    Bart Brown


  • Nick Mead |
    Nick Mead

    @Bart Brown (and anyone else still struggling with this problem), I've published a simpler solution to this problem here. Let me know if you still have any problems!


  • moviegourmet |

    I don't know what search term I used to finally bring up this page, but Hallelujah! I have searched on and off for over a year! Thank you!!!!!!!!!!

  • moviegourmet |

    I can't believe it - I followed the instructions and it worked ONCE!! Now I'm getting the same error message. I went to the "simpler solution" and I can't get the path to turn black. I've used the feature View Path Bar to see the exact path and it's still red. Ugh!!

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