Jump to content

Making Windows partition bootable

windows7 MBR GPT VirtualBox Booting

  • Please log in to reply
No replies to this topic

#1
Bautastein

Bautastein

    InsanelyMac Protégé

  • Members
  • Pip
  • 1 posts
Hi
 
The problem is the following: I have a mid 2012 27" iMac with no SuperDrive, and would like to install Windows using dual boot. I have an ISO image of Win7. I see there's an option in Boot Camp Assistant to install it via a USB Flash Drive, but I don't have one. Since I am sick I would have to order it online, and it would take maybe a week, and I'm a little impatient. I see there is an often recommended trick of installing Windows via VMWare to the physical disk, then switch the virtual machine off before it restarts, then restart the mac and boot into the new windows Volume. I don't have VMWare Fusion, but I tried it with VirtualBox instead. I then tried to set the startup volume to the new Windows partition, in System Preferences, and restarted, and got the following message:
 
No Bootable Device --- press any key to continue...
 
The message is taken from memory. So, I reckon there might be three ways from here:
 
1) Install rEFIt. I see almost all tutorials include this. I'm very squeamish about installing software that has low-level access and makes low-level changes to the system that might have consequences like the machine not booting at all. I'm not sure how much it changes the firmware etc., the stuff that I'm squeamish about. I also couldn't quite determine from the rEFIt/rEFInd websites whether it would solve my problem, and whether it would be necessary.
 
2) Try installing windows again via VirtualBox, but this time give VirtualBox access to the entire disk. Gulp! I'm squeamish about that too. Until now, I have only given it access to the partition where I want Windows installed, I suspect the Windows installer actually needs to put some boot code into the MBR records too. I suspect I would have to give it access to the entire physical disk for it to work. But, as I understand it, there is a trick that Mac OS X employs to make two partition map types work together. Perhaps there might be incompatibilities that won't be handled by installing Windows via VirtualBox, so that the entire disk could be ruined (or at least the partition tables). Therefore, I thought I'd ask here first. Here is the command I used to create the raw vmdk file for VirtualBox:
 
sudo vboxmanage internalcommands createrawvmdk -filename ./raw_hd.vmdk -rawdisk /dev/disk0 -partitions 4
 
By removing the last bit "-partitions 4", I'd give it access to the entire disk.
 
3) Get VMWare Fusion, and install Windows via it instead, like the tutorials say? Perhaps VirtualBox just ain't up to the task?
 
Or..... maybe I should just accept that squeamishness and hackishness don't go together, and order a USB flash drive online....
 
Partition Inspector from the rEFIt package (which I didn't install), says:
 
*** Report for internal hard disk ***


Current GPT partition table:
 #      Start LBA      End LBA  Type
 1             40       409639  EFI System (FAT)
 2         409640   1815536839  Mac OS X HFS+
 3     1815536840   1816806375  Mac OS X Boot
 4     1816807424   1953523711  Basic Data


Current MBR partition table:
 # A    Start LBA      End LBA  Type
 1              1       409639  ee  EFI Protective
 2         409640   1815536839  af  Mac OS X HFS+
 3     1815536840   1816806375  ab  Mac OS X Boot
 4     1816807424   1953523711  87  NTFS volume set


MBR contents:
 Boot Code: None


Partition at LBA 40:
 Boot Code: None (Non-system disk message)
 File System: FAT32
 Listed in GPT as partition 1, type EFI System (FAT)


Partition at LBA 409640:
 Boot Code: None
 File System: HFS Extended (HFS+)
 Listed in GPT as partition 2, type Mac OS X HFS+
 Listed in MBR as partition 2, type af  Mac OS X HFS+


Partition at LBA 1815536840:
 Boot Code: None
 File System: HFS Extended (HFS+)
 Listed in GPT as partition 3, type Mac OS X Boot
 Listed in MBR as partition 3, type ab  Mac OS X Boot


Partition at LBA 1816807424:
 Boot Code: Windows BOOTMGR (Vista)
 File System: NTFS
 Listed in GPT as partition 4, type Basic Data
 Listed in MBR as partition 4, type 87  NTFS volume set







0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

© 2017 InsanelyMac  |   News  |   Forum  |   Downloads  |   OSx86 Wiki  |   Designed by Ed Gain  |   Logo by irfan  |   Privacy Policy