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Can't boot to Windows 7 USB install disk MADE with BootCamp

128keaton

128keaton

macrumors 68020
Original poster
Jan 13, 2013
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Hey guys, frustrating issue thats got me hopping. I've been trying to install Windows 7 on an Early 2008 iMac. I enabled the USB install option in Bootcamp and selected my Win7 ISO (known good!). I rebooted but it never showed up. I've tried another USB port, another USB drive, another ISO. It doesn't show up in the boot menu (native, rEFIt, rEFIed) nor the startup pane. What the hell is happening?
 
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128keaton said:
Hey guys, frustrating issue thats got me hopping. I've been trying to install Windows 7 on an Early 2008 iMac. I enabled the USB install option in Bootcamp and selected my Win7 ISO (known good!). I rebooted but it never showed up. I've tried another USB port, another USB drive, another ISO. It doesn't show up in the boot menu (native, rEFIt, rEFIed) nor the startup pane. What the hell is happening?
Click to expand...

I've never had good luck with Bootcamp making me a bootable disk. I always make my flash drives bootable first and then install Bootcamp.

I use a software called Rufus on my windows machine. Works great.
 
MacOG728893 said:
I've never had good luck with Bootcamp making me a bootable disk. I always make my flash drives bootable first and then install Bootcamp.

I use a software called Rufus on my windows machine. Works great.
Click to expand...

I'll try that, I use that occasionally for other stuff, but now I'll try this method. I shall report back soon.
 
MacOG728893 said:
Great let me know.
Click to expand...

Hmm, its a GPT partitioned drive, it wouldn't show up in the option menu, but it would in the rEFId menu, but it errored on boot (no bootable drive found). Booting OS X to see if it show up in the 'Startup Disk' prefpane.
 
128keaton said:
Hmm, its a GPT partitioned drive, it wouldn't show up in the option menu, but it would in the rEFId menu, but it errored on boot (no bootable drive found). Booting OS X to see if it show up in the 'Startup Disk' prefpane.
Click to expand...

That's your problem right there.
Windows boot drives must be MBR.
Go back to Disk Utility and repartition it (not just reformat it) and then run Bootcamp again.
 
Another thing to note is that not all Intell Macs can boot from a USB Windows 7 Boot Camp drive easily or at all. Your iMac may be one of those models.
 
I'm pretty sure that usb keys don't really have boot sectors. they are bootable because the firmware of the usb key emulates the boot sector.

for example. if you took a dos 3.3 disk and copied
COMMAND.COM
IO.SYS
MSDOS.SYS

to it, with the hidden system attribute, the usb key would actually boot. because the usb key's firmware sees those files, and passes them to the computer.


i think u just format as FAT
and write the iso to usb using rufus or another utility it would boot without any other issues


http://pcsupport.about.com/od/file-folder/fl/burn-iso-usb.htm

here is a tech net link
http://blogs.technet.com/b/danstolt...elease-preview-or-other-operating-system.aspx

when i say usb keys don't have a boot sector, i think what i mean is that usb keys don't have a track 0, and track 0 is actually in the usb key's firmware that emulates track 0

if you copied the contents from the windows cd to the usb and included all system and hidden files, it probably would actually boot.
 
For Windows and other MBR native operating systems, there is a boot sector for USB drives. While it isn't a fully standard MBR sector, it does exist and if it is damaged or absent, the machine will not boot from it if it is running BIOS or a BIOS emulated firmware as the case with Intell Macs' EFI.
 
Intell said:
Another thing to note is that not all Intell Macs can boot from a USB Windows 7 Boot Camp drive easily or at all. Your iMac may be one of those models.
Click to expand...

Very possible, I might just have to wait for some new DVDs since mine don't want to be read or written to :p.
 
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