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I was trying to install Windows XP on a separate partition from my Windows 7 (RC) installation, but after the first reboot of the Windows XP setup, I get "Error loading operating system" and the system halts.

Here are the exact steps I followed:

  1. Installed Windows 7 on a clean drive - Windows created a 100MB system partition, then I created a 350MB partition for the O/S, and I left 125GB unallocated.
  2. Installed Windows XP in a new partition allocated from 125GB unallocated space.
  3. After first reboot of Windows XP setup, I get "Error loading operating system".

I attempted to fix the problem using the "Startup Repair" tool on the Windows 7 installation DVD, and although it found a "master boot record corruption" and fixed it, I still get the same error after rebooting.

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migrated from Jan 6 '10 at 10:13

This question came from our site for system and network administrators.

up vote 3 down vote accepted

Windows 7 would have to be the last OS installed. The XP bootloader may be unable to handle Windows 7, but the other way around is likely fine. Try fixing your mbr (/fixmbr) from a Win 7 recovery console.

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Thanks Xorlev, you set me on the right path. "Bootrec /fixmbr" at the Win 7 recovery console fixed the problem. – gdenning Oct 15 '09 at 14:38
You can also use BcdEdit which is good tool. – avirk Jun 13 '12 at 15:12

I can confirm that the XP bootloader does not handle Windows 7 well, and that even reinstalling XP over a HD that previously had windows 7 on it can be a hairy experience.

Standard practice for multibooting Windows is to install OS versions in order from oldest to newest, and so far as I am aware this may even be a MS recommendation, with other install orders being unsupported.

I would recommend to blow away both OSs and start from scratch again in the correct order (i.e. XP first).

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Windows 7 doesn't play nice with other operating systems on the same box unless they're also Windows 7. So you'll probably have more luck installing Windows XP first, and then putting 7 on another partition (oldest first). I haven't tried this, so it comes with a disclaimer.

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I dont think Windows 7 agrees with older OS's being installed after it. If its not too much work, I would recommend just blowing everything away, installing XP, then installing Windows 7 after it. I think thats your best bet.

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It took me 3 hours but I managed to get around the "error loading operating system" problem with installing windows XP to dual boot with a pre-existing installation of windows 7. I have posted my solution on my blog if anyone is interested. Installing Windows XP to dual boot on a Windows 7 system

Hope this helps.

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Install EasyBCD Free version (bottom of the page) in the OS that is bootable, run easy BCD and repair the Windows 7 bootloader, then add XP back into the Windows 7 bootmanager

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Always it is good to install lower version of the os first, After that you should install Higher version, means xp first then windows 7. if you do the reverse at that time you will get this type of problem. it replace your bootloader.

Because your newer operating system will always recognize and set the required parameters to co exist with the older one.

i dont no how to solve this one, once i also got the same problem.

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