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14

When GRUB is gone, so is the ability to boot into Windows. You would now need to boot from the Windows CD to restore the Master Boot Record (MBR). You can also use other boot CDs such as the Ultimate Boot CD for Windows, Bart PE or Hiren's Boot CD in case you don't have Windows installation media handy. Here are the steps: Boot from the Windows CD and ...


14

Since you mentioned GParted, try this: Launch GParted on the disk. If any partitions are mounted (as indicated by a lock or key icon), unmount them. Select Device->Create Partition Table. Click Apply. The disk should now use MBR. You can also create partitions within GParted, if you like; however, the Windows installer can do this automatically if you ...


11

Intel-based Macs all use EFI, and can only boot from GPT drives. Booting from MBR is supported by all non-Mac x86 PCs. Booting from a GPT disk requires UEFI firmware. (This requirement doesn't apply for using MBR/GPT on data disks; in that case, only OS support is necessary.) The MBR is 512 bytes in size; GPT can grow depending on partition count. MBR uses ...


11

If you have a Windows 7 Installation disk, you can enter Repair mode and use diskpart to accomplish this. From Windows 7 DVD, click Repair your computer when you see this screen: Then select Command Prompt in the Repair window: Once you've entered the command prompt, type diskpart to enter the utility. Type select disk # replacing "#" with the ...


10

You can inspect this with dd and file, e.g. for /dev/sda: root@rapunzel:~# dd if=/dev/sda of=/tmp/test count=1 bs=512 1+0 records in 1+0 records out 512 bytes (512 B) copied, 6.1994e-05 s, 8.3 MB/s Then you've got the bootsector in /tmp/test you can ask file what it thinks: root@rapunzel:~# file /tmp/test /tmp/test: x86 boot sector; partition 1: ID=0x7, ...


9

Wil's answer is vaguely correct, but isn't technically accurate. Yes, a drive does not need an MBR. Without one, you will be unable to boot from that drive, and you will not be able to create partitions on that drive. BUT... The term Master Boot Record is often used to refer to two things -- it is properly only the first, and commonly misapplied to the ...


9

Read through the first half of this answer to understand the basics of MBRs, VBRs (aka partition boot sectors) and boot managers. Now that you've read that, you understand that you need some boot loader in the MBR, or the BIOS can't boot from the drive. The BIOS loads code from the MBR, which then loads code from a VBR (or sometimes provides a menu of VBRs ...


8

When GRUB probes devices it makes a device.map file, you can find this in the same directory as your grub.conf. It will look similar to this: (fd0) /dev/fd0 (hd0) /dev/sda (hd1) /dev/sdb (hd2) /dev/sdc You are free to modify this as you see fit any time. Read more here.


8

Sector-size issues are becoming quite complex. Until late 2009, the vast majority of hard disks used 512-byte sectors, and that was that. In late 2009, disk manufacturers began introducing so-called Advanced Format (AF) disks, which use 4096-byte sectors. These first AF disks (and, AFAIK, all AF disks today) present an interface to the computer that shows ...


7

For this problem it's not actually an issue with the MBR. The AudoCAD forums you linked to had the following info: It's not a change in MBR. grub bootloader put it's stage2 code into the 2048 sectors after the master boot record. this harddisk area is not used by operating systems and resides before the first partion. between byte 3585 (0x0E01) and ...


7

Windows will install a master boot record on the first physical disk (\device\harddisk0). This may or may not correspond to the disk which contains the C:\ volume or the Windows system volume.


7

Hirens has the MbrFix tool. example: C:> MbrFix /drive 0 fixmbr /yes MBRtool is also on the Hirens disc


6

What exactly makes BIOS decide if a drive is bootable or not? The BIOS decides if a drive is bootable based on the 16-byte partition record, present after the MBR code area (held in a table starting at the 446th byte). The first byte in each partition record represents the drive's bootable status (and is set to 0x80 if bootable, or 0x00 if not). Some ...


6

Short answer: no. You can, however, image (also commonly called "ghost") the drive to another. Norton Ghost, Acronis and other tools exist to accomplish this. What does work however with Windows XP (not applicable to Vista and up) is starting the installation, letting the file copy finish. Then, delete everything the new installation created except the ...


6

I only know of three partition schemes: MBR, GPT, and APM. (These are the ones Apple's Disk Utility can create.) MBR (Master Boot Record) is used historically by Windows (and, therefore, by most computer manufacturers). I'm not certain if you can boot a Mac from an MBR disk; I don't think so. GPT (GUID Partition Table) is generally used in conjunction with ...


6

Use Disk Utility Options to set the partition type to Master Boot Record before you do dd.


6

This is pretty easy. Partition your disk, install Windows and Ubuntu. Use TrueCrypt on the Windows partition, which will encrypt Windows but leave Ubuntu unencrypted. You'll then find you can probably only boot into Windows, and then through the TrueCrypt bootloader. Sounds like you're there already. Say your disk is sda, with Windows on sda1 and Linux on ...


6

That command will remove the partition table. If you want to remove the MBR and keep the partition table: dd if=/dev/zero of=/dev/hda bs=446 count=1 See Wikipedia's MBR page for the MBR layout. The primary partition table starts at byte 446 (counting from zero).


6

No, your MBR is not working, but that's fine, because your Windows never used it in the first place. Your computer has the new UEFI firmware instead of BIOS, and it does not look for boot code in the MBR anymore – instead, it looks for the bootloader file in an "EFI system partition", and the firmware keeps a list of installed operating systems with ...


5

You can do it with Linux. Either boot a USB stick; or if Linux is already installed, you can rewrite the MBR as a "final act", which will make it inaccessible (until you reinstall Linux). First you have to identify the disk. In the Terminal: sudo fdisk -l to list the partitions. The disk will probably be either /dev/sda or /dev/hda. Then: sudo apt-get ...


5

Chances are the disk used to be a GUID Partition Table (GPT) disk. Such disks have partitioning data from sectors 0-33 (typically) and also in the last 33 sectors of the disk. If a GPT disk is repartitioned by a GPT-unaware utility, that utility is likely to replace just sector 0 (the MBR), leaving most of the GPT data intact. Technically, the disk is then ...


5

As Gilles already pointed out, grub rescue only has a few commands which allow you to load modules (e.g. from a grub rescue disk). In my case - booting from another source wasn't possible - the only option was to remove the hdd from the computer and use a cheap external hd case to connect the disk to another computer via USB. On that computer, I used MbrFix ...


5

Run Xubuntu from LiveCD or LiveUSB and install Boot-Repair. To install Boot-Repair, open up a terminal by pressing Ctrl+Alt+T and type the following commands: sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update sudo apt-get install -y boot-repair && boot-repair After installation, Boot-Repair will automatically ...


5

It looks like something has trashed your GPT data -- both the main data structures and the backup data structures. I don't know specifically what might have done this, but a buggy partitioning tool seems like the most likely culprit. Another possibility is that there's been some confusion over something like a RAID configuration -- if the disk was originally ...


4

If the drive won't boot, there's something wrong with the MBR or it's not there, so that's your "verification". However, the command bootrec.exe /ScanOs should display the list of active records the MBR. If there are none, then again, it's either missing or corrupt. Kruug's comment is correct in that if you improperly cloned the drive (for instance, only ...


4

The BCD is a file, named BCD, which lives in the Boot folder on the 100MB partition Windows makes before the main system partition during install (it's also possible you may have a Boot folder on your C:\ drive). It's a registry hive. It's mounted in the registry at HKLM\BCD00000000. bootrec /RebuildBCD only rebuilds this BCD file. Other bootrec options ...


4

You need to install the raid driver in Windows. For Intel, go to their downloads website and get the latest version of the Intel Rapid Storage Technology drivers for your system


4

Deleting the disk signature solved the problem. This can be done with the command dd if=/dev/zero of=/dev/sdb bs=1 count=4 seek=440 conv=notrunc in a linux shell with root rights. Background: Starting with Windows 2000, Microsoft writes a 4-byte value -the disk signature- into the MBR of each disk so that it can identify each disk. When two disks have ...


4

@Ramhound: Mac OS X only requires a GPT partitioning scheme to INSTALL, it will boot from MBR if your copy the OS to such a disk. @John: The simple answer is no, you can't. Here's why. You should not convert a Windows installation in place, you should instead install from scratch. This is one of those problems where you would spend more time making copies ...



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