Using the Windows 7 USB Download Tool with ANY .iso file

Randy Guthrie – Microsoft Academic Developer Evangelist

Update: Dec 15, 2014.  The Microsoft published tool mentioned below has been updated so it works with more file types. It has also been renamed to just the “Windows USB Download Tool”. 

As notebooks, netbooks and slates get thinner, smaller, and more power-conscious, optical drives that can read and write to a bootable DVD have now become a peripheral device rather than a built-in.  This makes it difficult to install software from a DVD for devices that do not have an optical drive, and even more problematic when you want to wipe the device and install a new OS. For these devices, installing software that you download as a compressed .iso file from a SD card or USB flash memory device is fast and cheap and a great alternative to buying an external optical reader. This is particularly useful to developers since most (if not all) of the software available via MSDN and DreamSpark is only available for download in the .iso format. Unfortunately there are not a lot of turn-key tools out there for burning from an .iso to a USB memory device. 

Microsoft has created the Windows USB Download Tool which is really nice if your .iso is a Windows operating system, but it fails when you try to use it with any other .iso. While searching for a work-around, I found this great blog post by Rafael Rivera with an explanation for why the Windows USB Download tool won’t work with every .iso file:

It appears there are two (possibly more) “navigation buoys” within UDF-formatted ISOs that point to important chunks of the image called Anchor Volume Descriptor Pointers (AVDPs). The first AVDP is somewhere near the top of the image. The last AVDP is located in what appears to be the last logical block of the image. (My guess is this is to support bi-directional reading.)

So assuming each logical block of the image is 2048 bytes large, one could also assume the last logical block is –2048 from the end of the file, right? Well, that’s what the tool assumes. It checks for the last AVDP at the start of the last logical block, doesn’t find it, and bombs out.

Rafael wrote a tiny downloadable utility program that will “fix” any .iso file where the last logical block does not have the AVDP so that the Windows 7 USB Download tool will work. Basically, you download the .zipped utility program and extract it. Then copy the .exe file to the same directory as your iso file, then run the utility in command mode pointing to the .iso file. In a second or so, your .iso file will be “fixed” so that the last logical block is the same size as the rest and the Windows 7 Download Tool will work. I tested it with the Windows 8 Developer Preview .iso I had downloaded and it worked like a charm.


Once you have the utility unpacked and in the same directory as your .iso file, launch a command prompt and change the directory to the folder where your files are, and then run the utility pointing to the .iso file:


In a few seconds your .iso file will be fixed! Then launch the Windows 7 USB Download Tool pointing to your .iso file and your USB memory device will be formatted and your .iso file unpacked so it will act just like a DVD. If installing an application, just navigate to the setup file and double click.  If you are installing an OS, then first you have to make sure your boot priority setting in your BIOS lists the USB device first, then DVD and finally your hard drive. Then restart your computing device and it should start booting from the USB device. As an added bonus, installing programs from flash memory devices, particularly USB devices goes MUCH faster than from DVDs.




Comments (53)

  1. Palermo4 says:

    Very helpful.  Thanks Randy 🙂

  2. Junaid says:

    when I run "c:usersufiadownloadsisoavdpcopy.exe Windows_7_Ultimate_64.iso" in "admin" cmd

    it gives me error that 'isoavdpcopy.exe' is not recognized as an internal or external command, operable program or batch file.

    tried isoavdpcopy with and without ".exe", but the result is same

    Both file are in same folder

    can you tell what am I doing wrong?

    vista ultimate SP2

  3. Thee says:

    I am running vista ultimate SP2

    And it works but i move all of my files to c:isoavdpcopy.exe Windows_7_Ultimate_64.iso

  4. Rahul says:

    i dis as said. But when i click the utility program it just flashes and goes back tell me what am i doing wrong ……PLease Help

  5. Homer says:

    I got an Error after "successful" Fix of the ISO-File with the last "Windows7-USB-DVD-tool" with Error-Message "The selected File is not a valid ISO-File"

  6. randguth says:

    Update: Windows 8 will now mount an .ISO file directly by right mouse clicking on the file, and then clicking "mount". You can then run the setup file directly from the OS without "burning" the .iso to a DVD or USB memory device. Win!

  7. Joseph Bolin says:

    I am getting ERROR: Specified ISO is read-only.

  8. randguth says:

    Can you right-mouse click on the file and change the property?  Try unchecking the box in the Properties windows that says "Read-Only".

  9. manish4544 says:

    hi! i tryed and ERROR: Specified ISO is read-only.

  10. Tumbleweed_Biff says:

    Attempted to use on a couple of different iso's without success. Process says "copy successful" but the Win 7 USB says not a valid iso. One of the iso's I used this on is for Win XP Pro. Too bad, would have been a very nice tool/fix if it worked.

  11. randguth says:

    Looks like either the utility or some other part of the process has changed. Since I didn't invent the utility, I can't "fix" it or comment on why it doesn't work. The good news is that Windows 8 at least lets you mount iso files directly, and you can run most installs now from the OS, including upgrades.

  12. OldMX says:

    Worked like a charm here, on a heavy modified .iso of windows vista business with sp2 and a 8gb corsair usb drive.

  13. orangeisnon says:

    My question is why you would need a program for this in the first place.  I have installed operating systems, from Windows 2000 through 8 (and all kinds of Linux), without using a single program.  All that you need to do is extract the .iso to a removable disk, reboot, and boot from the disk.  Why do you need a program?

  14. Casey says:

    Worked well for me.  I had Windows 7 and still got the invalid iso message.



  15. Amjed says:

    great dude. Worked for me on the first attempt itself. What about windows xp? is there any tool like this?

  16. DURAISAMY says:

    To install windows 7 through pen drive no need to download any tools please folly the steps and make usb disk as bootable step 1 go to command prompt in windows 7 system type DISKPART

    then type LISTDISK anb select the disk which you make it as bootable  now type CLEAN. Now the type CREATE PARTITION PRIMARY and format the disk using command FORMAT =  FS  NTFS QUCIK

    and finally ACTIVE

  17. Sinisa says:

    Great! I solve some issues with this tool. Thanks

  18. las says:

    Dear randy,

    Thanks for app.I found out why it gives read have to add whatever name.iso in comandline.Missing .iso extension at the end of command   gives that error

  19. sahban says:

    DURAISAMY your solution worked for me. Thank you.

  20. Umm says:

    "Unfortunately there are not a lot of turn-key tools out there for burning from an .iso to a USB memory device."

    Sure there are. They're just only available on Unix-like operating systems. When is Microsoft going to add this- yet another feature that Unix-like operating systems have had for over 20 years- to the standard available tools?

  21. Prithvi says:

    The link to the file is dead.

    As mentioned by others, no need to use all these tools.

    Format the pen drive with NTFS quick format.

    Simply extract the .iso file by using PowerISO into the pen drive.

    Boot normally and choose USB-HDD in boot menu.

  22. Bruno says:

    The solution for ERROR: Specified ISO is read-only is delete the space of iso file

  23. Ged1s says:

    in cmd said copy successful but in MS usb tool still says same error….

  24. hmmm idiots says:

    Why can't people actually be helpful instead of trying to boast knowledge. It actually shows how little knowledge you do have… To the guy that said unix tools have done this for 20 years. here's some school for you. Flash drives let alone usb ports haven't existed for 20 years and you almost predated the ISO 9660 format…..

    Then the two tools who said just extract the iso to usb and boot.. Ummm either you purposely left a step out or are just idiots.. FIRST you have to make the flash drive bootable. Which one poster was nice enough to detail.

    The idiocy of the internet makes it so hard for people.. why can't you just keep your mouth's shut.

  25. nick says:

    for those to whom it said error read only, dont worry, it has already worked jus transfer it now

  26. A user says:

    the download link is dead, please fix that or remove the link and instruct the reader to Google for it

  27. randguth says:

    Fixed the link. Thanks!

  28. Lissa says:

    First and foremost, I am NOT a computer novice by any means.  However, in attempting to perform the required steps using the iso workaround tool, I simply have a command prompt that reads " Windows 7 ISO AVDP Copy Tool v0.1 Copyright (c) Rafael Rivera Within Windows –".  I have no clue what my next step is.  In order to REACH this step, I had to r-click on the iso file and choose "Open with…." and then choose the iso copy tool.  I am still getting the "iso file is not a valid image file" message when trying to use the windows 7 usbdvd download.  What am I missing here?  And please bear in mind, I DID specify I am not a novice……………………

  29. Lissa says:

    P.S.  Please be very detailed in instructions.  

  30. Don Wallis says:

    Thanks so much. Worked a charm on my 'invalid' ISO file created with Daemon Tools. The Microsoft program Windows7 USB DVD… is now happy. Brilliant!

  31. Martin Henning says:

    FYI: The direct link to tool is broken but it still can be downloaded from Rafael Rivera original blog post.

  32. Mohammad Fazlur Rahman says:

    I tried to do the same for my WindowsXP 64 bit installation. I tried to make a USB bootable drive using my pen drive and a WindowsXP 64 bit *.iso file. I am running Windows7 64 bit right now. I got the msg that copy successful and then I started using Windows7 USB too. It started copying files but at the 96% it failed and msg came "ss". I tried again a few more times and exactly at the same location 96% I got the mesg ever time I tried. So my job is not done. Can you please suggest what could be the reason for this. thanks in advance

  33. Mohammad Fazlur Rahman says:

    I forgot to put the message I received in the UST tool execution… it is:

    Status: We were unable to copy your files. Please check your USB device and the selected ISO file and try again.

  34. Dallas says:

    I kept getting the error "ERROR: Specified ISO is read-only using the rafael utility

    The only thing I did correct this was rename the iso to WINDOWS7A then press enter.

    Ran the Rafael Rivera tool an it worked. said copy successful

  35. Aedan says:

    Hi Guys, found the tool on the old forum as the link here is dead.

    Put my ISO in a folder with the tool double clicked, black window appears quickly, then vanishes, ISO still wont work with Windows 7 USB DVD Download Tool. Any advice on how to get this going?

    Kindest regards


  36. Jim Barr says:

    Thanks! Spent 4 hours on this and found nothing to help. This did it. Much appreciated.

  37. flon says:

    ran the program but didn't do anything.  I then dragged the iso file onto the isoavdpcopy.exe file and it did its thing. now it works. hope this helps someone.

  38. Santiago says:

    The "specified ISO is read-only." error happened to me when i didn't typed .iso at the end of the command. Try to put it, it worked for me.

  39. download fix here says:

    Link to the fix in this article is dead.  Download link avail here…/use-the-windows-7-usbdvd-download-tool-with-custom-isos

  40. James says:

    Do you realize that your image of the command prompt names the file as a ".edu" file? When I changed it to ".exe" it worked. I am a novice, but I assume this was an error.  

  41. Randy says:

    Worked well. Thanks. Person who had the read only error has to right click the iso and uncheck the read only property attribute.

  42. JA says:

    im desperately in need of help in reguards to this tool.

  43. Martin says:

    Didn't work for me I'm afraid.  Windows 7 32 bit iso created with IsoCreator.  Did process the ISO and modify it but still "Selected file is not an ISO".  Will try another ISO program and report back.

  44. Kent says:

    run it in command window or drag the iso to the tool, but nothing happen except that the cursor is flashing. can anyone help


  45. enigma_x says:

    Link to the tool at Microsoft

  46. gullfounder says:

    Its seams that link to your tool is not working any more.

  47. Damion Jones says:

    Keeps telling me the ISO is READ ONLY

    Its not. I have tried all kinds of attributes, and tried from all kinds of sources, and filesystems.


  48. Abdul Ahad Ali says:

    Hi, It didn't work for Windows XP iso. I put the both iso file and isoavdpcopy.exe in a same folder, as soon as I run the .exe file, it pops up and then disappears, getting the same error by Windows 7 USB tool.

    On an another article, I read to change the properties of iso file to UDF enabled with both Joilet enabled and disables, I've also done that Windows XP iso but the error persists

  49. anon says:

    The link has not been updated and the download tool is still from 2009 and doesn't work….

  50. Zak Tucker says:

    Thank you 😀

  51. oohgodyeah says:

    Links to the tool download and the original blog post do not work.