Fixing “Select CD-ROM Boot Type” when installing 64bit Windows

If you have to install 64bit Windows Vista, 7 or Server 2008 than you may come across an error that goes “Select CD-ROM Boot Type“. This will happen when you try to boot from the hard drive after the Windows DVD has copied over some of the files during the first phase of installation. We searched the internet and came across hundreds of people begging for assistance over this error and we have the solution here and tested it recently with Windows 7 64bit Enterprise.

  1. Take your CD/DVD/ISO and copy all the contents to your computer.
  2. Download OSCDIMG.exe from here: CLICK HERE FOR DOWNLOAD
  3. Now load up the command line and run the following command “oscdimg -n -m -bc:\windows7contents\boot\ c:\windows7contents c:\newwindows7dvd\newwindows7dvd.iso
The program will produce for you a brand new ISO to use that will not give you the “Select CD-ROM Boot Type” error in the future.
UPDATE: The link to download the OSCDIMG.exe has been updated to a working one- 30/03/12
Share on social media: Email this to someoneShare on FacebookShare on Google+Share on LinkedInPrint this pageShare on RedditTweet about this on TwitterShare on Tumblr


  1. Just install rEFIt. MUCH easier!

    • does that work on the newest retina macbook pros with mountain lion?

    • Can you elaborate? rEFIt by itself is just a menu and maintenance toolkit for EFI-based hardware. How exactly are we supposed to use rEFIt to run 64-bit Windows? Is there a special option on rEFIt to do that?

  2. The third instruction is a bit vague: “Now load up the command line and run the following command oscdimg -n -m -bc:\windows7contents\boot\ c:\windows7contents c:\newwindows7dvd\newwindows7dvd.iso”.

    I ran command prompt and typed that in, and got: “oscdimg” is not recognized as an internal or external command, operable program or batch file.

    I also tried opening the oscdimg file and it flashes up and disappears.

    There are some steps missing here, if you can flesh it out a bit more it would help a lot! Thank you.

    • Hi,

      I read this here and know what is wrong:

      “I ran command prompt and typed that in, and got: “oscdimg” is not recognized as an internal or external command, operable program or batch file.

      I also tried opening the oscdimg file and it flashes up and disappears.” – Lachlan

      oscdimg is not to be run by double clicking on it at all. You have to execute it from the command prompt. You are opening up the command prompt and entering in the command that is posted right? Well you first have to make sure that you are executing it from the same folder that your oscdimg is located. If your oscdimg is located in C:/Users/John/Documents/Downloads/oscdimg.exe then you have to first type in the command: cd C:/Users/John/Documents/Downloads

      You have to check your own machine to determine where you have that file located. One easy trick is just to place the oscdimg.exe in your root C:/ directory and execute it from there by then doing the command: C:

      Typing that in should bring you to your root C: directory and then you can type in oscdimg -n -m -bc:\windows7contents\boot\ c:\windows7contents c:\newwindows7dvd\newwindows7dvd.iso”

      I hope this helps you. Reply back if you need some more.

      • Hello,
        I am currently having the same problem as user “lachlan” above, but my exe file is in my root C:\ directory, just as you suggested. I am using the command prompt, but I am still getting the same error message. Is there any other place I could run the exe from? Any idea what I’m doing incorrectly?
        Thank you!

        • In the command prompt window box. Are you in the correct directory? It is required that you are in the right directory inside of the command prompt that the .exe file is located in.

          You can also put that .exe file into your C:/Windows/ or even C:/Windows/System32
          An .exe file in those folders should be able to be run from the command prompt no matter what. I did not recommend this just in case it spooked people about taking some .exe off the ‘net and slapping it into their more OS-critical directories.

          • Thank you for your swift response!
            Well I put the exe into my windows folder in my C: drive. I open the command prompt, but it seems I cannot change the directory from C:\Users\Neumann,nevertheless I got this to run:
            OSCDIMG 2.54 CD-ROM and DVD-ROM Premastering Utility
            Copyright Microsoft etc…
            But right under it I get an error: Could not open boot sector file “c:\windows7contents\boot\
            Error 3: The system cannot find the path specified.
            Did I do something wrong in copying my 64bit files maybe? Are they supposed to be copied to a certain/same place?
            P.S. Sorry to be such a nuisance..

          • Its alright man,

            Yeah check your directories to where you have copied these files to.
            lol… I’m a bit embarassed to admit this now but I have not done this in AGES so this is mostly from memory. Reply back if there are any further problems. I will look over my own notes again.

  3. NEVERMIND! Had to rename a few files and create a few folders but the program seems to have worked. Thanks for your help, fingers crossed everything works from here on out.

    • Excellent :)
      It always seems to work out in the end!

  4. Do I do all the command prompt stuff from with in osx Terminal, or from windows command prompt? The instructions dont say which?

    if it is the latter – how do I get to the command prompt, as when I turn the pc on I get the following message and can do anything:


    Select CD-ROM Boot Type: _


    • Hi ger,

      These commands are done in windows. Use a virtual machine or another windows box to do them.

  5. I guess the only thing you forgot to explain is that you have to create the directory ‘windows7contents’ first and place the files from the .iso in it and then create the ‘newwindows7dvd’ directory as well…

    • Thanks for the tips, works well for me. and make sure that you put these 2 new folders in C:/, only then the command works.

  6. Thank you. This has solved my problem with my MacMini. Works great.

    Does something similar exist for Windows 8,1?

    • Are you having similar troubles with Windows 8.1?

      • Hi,
        yes, I’m having the same problem with Windows 8 64-bit.
        Does somebody have a solution for this?

        Thank you!

  7. Thanks for all your help here..
    I have followed your directions and successfully created the newwindows7dvd.iso and copied it to a usb stick. However, when using Boot Camp Assist, it creates a partition, but will not recognize the usb as a boot drive. Booting from the Windows Install DVD gives me the “Select CD-ROM Boot Type” error. Do I need to put the iso somewhere else other than on the usb stick?

    2009 15″ MacBook Pro. 2.4 GHz Intel Core 2 Duo. OS X 10.9.1 Mavericks

    • When you say you copied the ISO to a USB stick, how did you perform that?

      • I went into Terminal and changed the permissions to allow my MBP to write to a USB drive. That change brought up the check box in Boot Camp. However, as mentioned, my particular MBP will not recognize a USB boot drive nor a Windows7 DVD while using 10.9 and Boot Camp 5. The solution is either to replace the HDD with a SSD OR revert to OS 10.6 – 10.8 and Boot Camp 4, then once the partition and Windows is installed, re-upgrade to 10.9. Pain in the A** that is.

        • Ok, so you already have 10.9 installed. You are using boot camp assistant to create the installation USB from the ISO but then the computer will not boot from the USB, correct?

  8. Thanks, worked a treat on our iMacs and Win8.1×64

  9. Hi
    In my case everything works fine but it cant create the iso file.
    unable to create file … bytes.
    ERROR 3
    Whats wrong?

    • Are you certain it was error #3? I would have thought it would be #5 due to the “bytes” part being mentioned there.
      Well anyways, try running the cmd.exe as an administrator. Search for the cmd.exe, right click on it and select RUN AS ADMINISTRATOR

  10. I found the Problem.
    Error 3 means the directory wasn’t found. I had to create the folder.
    Thanks for the quick answer! :)

  11. Super, everything work. After reading a lot of unecessary (un)solution this post work.


Submit a Comment

Your email address will not be published. Required fields are marked *



You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>