recover boot Windows Longhorn

[jaclaz]

With all due respect, you seem like mixing all together a lot of things of which you have only a minimal understanding.

It is very unlikely (please read as "it won't work) that you will ever be able to start a later OS with the boot files of a previous one.

As well your attempt (if I get right what you attempted doing) to repair a Windows 7 boot using Vista files/tools is completely futile.

It is the first time I read about partitions disappearing when deleting the boot files, it makes very little sense, the NT 5 boot files (NTLDR, NTDETECT.COM and BOOT.INI) are completely offline/non accessed once the OS is booted. the NT6 file BOOTMGR is as well completely offline/not accessed BUT the \boot\BCD (which is actually a Registry hive) is instead online when the os is booted as it is mounted as HKLM\BCD00000000, so only deleting this latter file may (though I doubt it) create issues (like preventing the deletion or crashing) but I cannot see how it can modify anything connected to partitioning/filesytems.

Partitions DO NOT disappear, what may happen is that data is corrupted/changed in the MBR partition table, the Magic Bytes become invalid or - much more rare and the symptom is having RAW partitions - that some data in the PBR is corrupted/changed.

It is possible, since you are using (why) XP on a disk with partitions aligned to megabyte (2048 sectors) that it corrupts something, but it is unlikely, the only reports we have is about the XP disk manager that corrupts logical volumes inside extended, never primary partitions.

About this there are only two "conventions" about disk partitioning:
1) up to XP partitions start and end aligned to heads and cylinders (and since the most common HS geometry is 255/63 this means that first partition starts on 0/1/0 - i.e. 63 - and end on n/254/63)
2) starting from Vista partitions are aligned to whole megabytes (actually mebibytes) i.e. 2048 sectors x 512 bytes each = 1048576 bytes, the first partition starts at 0/32/33 - i.e. 2048)

Clusters are related only to filesystems and their size have nothing to do with disk partitioning.

The NTFS default cluster size is 4096 bytes (no matter which OS, on any practical size of a volume), FAT32 cluster size affects (or is affected by) volume size, the FAT32 default cluster size of 4096 bytes cluster size applies only up to around 8GB, larger volumes will have larger cluster size.

If you want to troubleshoot the issue, you will need to learn how to make backups/copies of the MBR and of the PBR's and compare them in order to pinpoint what actually changes.

When you use "automagical" tools (easus/eassos/etc,) you don't know what they do, for all we know they might fix the actual issue but create another one.

About bootrec, you have to understand what it does:

https://ss64.com/nt/bootrec.html

Bootrec /fixboot writes new bootsector CODE, leaving the DATA in it untouched
Bootrec /fixMBR writes new MBR CODE, leaving the DATA in it untouched

so if the issue is with either the MBR or PBR DATA, they won't do anything.

The above link explains also how to use the bootrec /rebuildBCD (i.e. making a backup and then deleting the existing BCD in order to force the tool to completely rebuild a new BCD), still, given the mixing of files and operating systems, it is entirely possible that the installed OS is not detected or not detected properly, so often it is needed (though they both need some experience) to use BCDboot and/or BCDedit manually, in any case you must use the tools coming from the exact same OS you are trying to boot/repair.

A possible alternative (easier to use because it is GUI, but that still needs some knowledge of the way the BCD works) could be BOOTICE:

http://reboot.pro/files/file/592-bootice-v1332/

jaclaz

[Cixert]

Some nuances about my previous comments.
The versions that start Windows with Bootmgr+NTLDR are the Shorthorn versions "Based Longhorn"
Since although the installer is Bootmgr these versions are really NTLDR.

On the other hand, Longhorn Pre-Reset from 4000 to 4093 use a 32-bit installer but these are NTLDR and not Bootmgr implements.

Longhorn Post Reset, at least between versions 5048 and 5112 install bootmgr, but are also starting from NTLDR version 2005 (required*). These versions boot from both methods but these only install bootmgr.

The latest Longhorn version that can be installed in Fat32 is 5001. That is, it coincides with the last one that NTLDR has.

Edited April 1, 2023 by Cixert
*required ntldr version 2005 (ntldr not ok version 2003 and not ok version 2008)

[Cixert]

On 3/26/2023 at 2:28 PM, jaclaz said:

With all due respect, you seem like mixing all together a lot of things of which you have only a minimal understanding.

It is very unlikely (please read as "it won't work) that you will ever be able to start a later OS with the boot files of a previous one.

As well your attempt (if I get right what you attempted doing) to repair a Windows 7 boot using Vista files/tools is completely futile.

It is the first time I read about partitions disappearing when deleting the boot files, it makes very little sense, the NT 5 boot files (NTLDR, NTDETECT.COM and BOOT.INI) are completely offline/non accessed once the OS is booted. the NT6 file BOOTMGR is as well completely offline/not accessed BUT the \boot\BCD (which is actually a Registry hive) is instead online when the os is booted as it is mounted as HKLM\BCD00000000, so only deleting this latter file may (though I doubt it) create issues (like preventing the deletion or crashing) but I cannot see how it can modify anything connected to partitioning/filesytems.

Partitions DO NOT disappear, what may happen is that data is corrupted/changed in the MBR partition table, the Magic Bytes become invalid or - much more rare and the symptom is having RAW partitions - that some data in the PBR is corrupted/changed.

It is possible, since you are using (why) XP on a disk with partitions aligned to megabyte (2048 sectors) that it corrupts something, but it is unlikely, the only reports we have is about the XP disk manager that corrupts logical volumes inside extended, never primary partitions.

About this there are only two "conventions" about disk partitioning:
1) up to XP partitions start and end aligned to heads and cylinders (and since the most common HS geometry is 255/63 this means that first partition starts on 0/1/0 - i.e. 63 - and end on n/254/63)
2) starting from Vista partitions are aligned to whole megabytes (actually mebibytes) i.e. 2048 sectors x 512 bytes each = 1048576 bytes, the first partition starts at 0/32/33 - i.e. 2048)

Clusters are related only to filesystems and their size have nothing to do with disk partitioning.

The NTFS default cluster size is 4096 bytes (no matter which OS, on any practical size of a volume), FAT32 cluster size affects (or is affected by) volume size, the FAT32 default cluster size of 4096 bytes cluster size applies only up to around 8GB, larger volumes will have larger cluster size.

If you want to troubleshoot the issue, you will need to learn how to make backups/copies of the MBR and of the PBR's and compare them in order to pinpoint what actually changes.

When you use "automagical" tools (easus/eassos/etc,) you don't know what they do, for all we know they might fix the actual issue but create another one.

About bootrec, you have to understand what it does:

https://ss64.com/nt/bootrec.html

Bootrec /fixboot writes new bootsector CODE, leaving the DATA in it untouched
Bootrec /fixMBR writes new MBR CODE, leaving the DATA in it untouched

so if the issue is with either the MBR or PBR DATA, they won't do anything.

The above link explains also how to use the bootrec /rebuildBCD (i.e. making a backup and then deleting the existing BCD in order to force the tool to completely rebuild a new BCD), still, given the mixing of files and operating systems, it is entirely possible that the installed OS is not detected or not detected properly, so often it is needed (though they both need some experience) to use BCDboot and/or BCDedit manually, in any case you must use the tools coming from the exact same OS you are trying to boot/repair.

A possible alternative (easier to use because it is GUI, but that still needs some knowledge of the way the BCD works) could be BOOTICE:

http://reboot.pro/files/file/592-bootice-v1332/

jaclaz

I have little knowledge about Windows NT6 start. This is evident.
I am now obliged to use an application that is no longer compatible with XP by imposition of the Government of Spain (Autofirma 1.8) to be able to send official documents to the country's administration.

Before using any superior version of Windows 2003 on my personal computer, the first thing I want to know is how they start.
And not vice versa. Use these and these not start. Or what is worse, that the data of my main computer are erased.

With all respect for who knows more, although some people have less knowledge can contribute a lot, if they work with collective intelligence. Well, all people have different points of view.

I am now doing tests in Windows Seven.
I have restored a backup copy of the starter boot.
I try to repair the installation from the Windows Seven console on another computer.
I have connected the hard disk by USB.
I follow the official steps, but the installation is not repaired.

Edited March 30, 2023 by Cixert