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I have a dual boot system with Windows XP Pro and Windows 7. Following are the contents of my system's boot.ini.

;Warning: Boot.ini is used on Windows XP and earlier operating systems.
;Warning: Use BCDEDIT.exe to modify Windows Vista boot options.
[boot loader]
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /NOEXECUTE=OPTIN /FASTDETECT

I just want to know about first two warning lines, whether these two lines are always present in dual boot system when the boot process is different for installed operating systems, for example xp + vista/w7 or windows2000 + vista/w7 etc?

Can we decide on this warning that a system is dual boot or is there any other reliable way?


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up vote 1 down vote accepted

Boot.ini is used by the Windows XP bootloader.

When you install windows 7/Vista, it overwrites the Windows XP bootloader with the 7 Bootloader. When the system starts, bootmgr is responsible for displaying the os selection screen. If you select Windows XP, it then passes execution to NTLDR. At no time is the windows XP bootloader (NTLDR) aware it's in a dual boot setup.

It looks like the warning in your boot.ini file was added by a boot-editing utility. On my dual boot XP/7 machine, it does not have that warning, so I would imagine it is not a reliable way to determine whether the system is dual boot.

The only reliable way I can think of to determine if a system is dual/multiple boot would be to look at the bootloader's configuration files. You would have to know what bootloader the system is using, based on the contents of the bootsector of the hard drive.


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