Windows 10 install Mac 32bit EFI, working FIX "select cdrom boot type"


macrumors newbie
Original poster
Dec 28, 2019
hi, ive written a working guide to fix that select cdrom type error, originally u can find it here.
show under "Create a Win10 install DVD:"

Create a Win10 install DVD:

1. Download Windows 10 x64
2. Open drive "C:" and create the following folders:


3. Download oscdimg.exe and copy this file to "winexe"
4. Unzip your Windows 10 ISO into "windvd".
5. Open command prompt and enter the following commands:

cd c:/winexe
oscdimg -n -m -bc:\windvd\boot\ c:\windvd c:\winiso\win10x64.iso

6. As soon as it's done you have the file "win10x64.iso" in the folder "winiso" which you burn on DVD now
7. Remove all HDDs from your MacPro except those you want to install Windows on.
8. Insert the burned DVD and install Windows as usual.

It's necessary to use a Win10 Pro, so that both processors are recognized that you have installed!

I uploaded 3 customized isos:

1. windows 10 x64
requires double layer blank

2. windows 10 x64 Lite
slightly reduced so that it fits on a 4.7 GB blank, e.g. languages and fonts have been removed

3. windows 10 x86
tested on my imac 7.1, with the normal windows 10 x86 he version this "select cdrom boot type" reported, according to guide it now works correctly

would be great if someone could test the x64 versions on MacPro.
(or other macs with 32bit efi and 64bit CPU)
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