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I installed Ubuntu on a free partion on a computer which had Windows 7 installed first, and Windows 7 won't boot. Usually installing linux after windows is recommended, but Windows 7 complains about there being a problem with its boot process.

How do I repair Windows 7 to boot correctly while maintaining grub to boot Ubuntu?

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Post more information! What's the specific error message? What partition was 7 originally on? What is the current partition structure? What are the contents of menu.lst? – CarlF Nov 10 '09 at 0:55
I'm sorry, I'm trying to do distance support, and I can't get much information. I just wanted to know if this was a well known problem. Thanks – user17441 Nov 10 '09 at 9:31

Windows 7 likes to be the main OS on a dual boot system. Your boot manager is the problem. Either use the Windows CD or your Ubuntu CD to go and rebuild your boot manager.

Good luck.

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Results may vary. Using GParted I resized my windows partition (C:\ - /dev/sda2). I also moved it to the end of the drive. I then resized my "windows-boot" partition (/dev/sda1). The one that Windows 7 made during install. I don't remember why I resized this partition, but I did.

And then I proceeded to install Ubuntu 9.10 with one swap partition and one ext4 partition for root. Both of these together used up the space on my harddrive between my windows partitions.

Finally, when I tried to boot into windows, I got the error message that I believe you are describing. Unfortunately I cannot recall its exact wording. I simply put the Windows 7 CD in as it requested, booted with it, and followed the on-screen instructions to run the repair. After doing so I still had grub, Linux and Windows both worked.

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I do not recommend using fixmbr! It has completely screwed up my partition tables multiple times in the past. That thing is awful. Why not just grab a new bootloader such as Lilo? This ships with Slackware, but should boot any kind of Linux or Windows.

Edit: Well I guess your thing worked. I've had a bad experience with Window's mbr fixing, though.

Good luck,


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You can use the Windows 7 CD and go to Repair, then go to Command Prompt.

If your Windows is in your C: drive, you can enter these commands:

bootsect /nt60 C: /mbr


bootsect /nt60 SYS

if you're unsure of which disk has Windows in it. This command will search for the system files.

After you're done, type exit. Then reboot the computer. It should reinstall the NTLDR which is the bootloader for Windows.

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