In addition to the disk signature the BCD also holds details about the location of partitions on a hard drive, which is also used by bootmgr to find the whereabouts of winload. If a partition's starting point on a drive its offset has moved, then bootmgr will not be able to find the partition and again will not be able to locate winload. This is covered in more detail on the Vista's Boot Files page. How to fix the BCD to cure a winload. It can generate only a few error messages, which you can see after the bootcode and before the disk signature.
The Vista bootcode in yellow in the MBR has grown in size slightly over that of XP, but still only occupies no more than the space before the disk signature on the very first sector of the drive.
I have looked for but not found one single byte in any of the free sectors between the MBR and the first partition. The purpose of the extra code was not made clear but it seems it is mostly to do with the BitLocker drive encryption system.
This MS white paper asking computer suppliers not to hook their recovery systems into the MS bootcode gives some insight. Windows NT operating systems will remember the drive letters that have previously been assigned to partitions and drives.
This differs from Win9x where drive letters are assigned on every bootup in a default order as the partitions and drives are discovered, which means changes to partitions or the adding of drives can cause letters to change. With NT the current hard drive partition drive letters can be maintained by linking them to a partition by using a unique number that is assigned to each partition and stored in the Windows registry.
This unique partition number is generated from the disk signature of the hard drive and the partition offset. On Windows bootup the partition number is compared with the disk signature and if they match then the partition will be assigned the same drive letter that had previously been allocated to it. If a disk signature is changed then Windows unique partition numbers become invalid.
They no longer match the MBR disk signature and therefore drive letter assignments are lost. On first reboot after a signature change each partition on the affected drive will have its unique number recreated to match the new disk signature, then be reassigned a drive letter.
These reassigned letters may not match the originals and so your drive letters may change. Any help sould be welcome, so I can eleminate at least one boot-selection menu Hopes somebody has an idea how to fix this I tried also after te move of my post to correct my disk-configuration : bootsect. Mac OS I want to modify the Vista-Boot-menu. This really should be your first stop when messing with BCD stuff.
INI file, and Vista reads it once. It just won't work COM , because the second XP-version was just dumped on the second disk using a ghost of another machine Yes, VBPro does "allow" you to make the entry, however, this is for maintenance purposes in case your XP install boot entry gets corrupted somehow and you need to re-enter it. If Microsoft had picked an offset of any even number of sectors divisible by the size of a new large-sector, wouldn't that solve any "misalignment" issue?
So why not simply pick an offset of 32, 64 or even KiB? Did Microsoft really want to be sure you could continue to use your Vista OS on drives with even much larger sector sizes? The typical Vista partition table one with only a single Vista partition will appear like this on current drive models:.
For technicians, it may take some time getting used to seeing a Starting CHS triple of 0,32,33 instead 0,1,1.
These values will also appear strange in a disk editor as show below where the hex equivalents of the Head and Sector values are 20 h and 21 h; the whole entry appearing as: "80 20 21 00 07 FE FF FF 00 08 00 00 00 88 82 01". This offset of sectors was chosen to ensure no matter how large sector sizes would become, the OS would still be aligned evenly with a disk's sectors. Thus, Vista and Windows 7 would still be aligned correctly if they were installed on disks having sector sizes of 8,bytes a sector offset or even 16,bytes a sector offset.
We did, however, find a very useful new feature in Windows Vista related to boot records and booting: Its Disk Management utility now has the ability to both shrink and expand partitions; just like Partition Magic can do for previous Windows versions. We'll be presenting a detailed page about this in the future. For our Windows Vista install, all the bytes of the Vista MBR's code were also contained inside the following files listed by location, alphabetically; with offset to first byte of the code.
In each case, there will be a full bytes that comprise the MBR code the location for the NT Disk Signature and the byte Partition Table are all zero-filled, the last two bytes being 55h followed by AAh : 1. Figure 2. A premium upgrade adds free tech support and the ability to resize dynamic volumes. It won't hot image your drives or align them, but since it's coupled with a partition manager, it allows you do perform many tasks at once, instead of just cloning drives.
You can move partitions around, resize them, defragment, and more, along with the other tools you'd expect from a cloning tool. Shred vs. What is the Difference? Let it manage your storage drive: resize, format, delete, clone, convert, etc. Screen Recorder. Transfer Products. File Management. More Products. Workable Solutions Step-by-step Troubleshooting Fix 1. Full steps Fix 2. Full steps. EaseUS also provides 1-on-1 remote assistance to fix the boot issue.
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