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I installed ubuntu 11.10 but it doesn't work properly, when I choose ubuntu after I turn my pc on it just shows me a purple screen and I can never enter ubuntu.

I want to delete it and instead install the new 12.04 but every tutorial for deleting a Ubuntu dual boot says I'll need a Win 7 CD/DVD to fix the MBR. I don't have a Windows 7 DVD how can I get ubuntu uninstalled and then fix the MBR?

Do I really have to try and get a Windows 7 DVD? Does anyone know where I can get such a thing? Hoping there's a work around that doesn't require a windows 7 DVD. Thank you in advance.

Thank you in advance!

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up vote 3 down vote accepted

You DO NOT need Windows disks and you DO NOT need to uninstall the previous Ubuntu in order to install a new version. You also do not need to boot into Windows to remove partitions. Just boot from Ubuntu 12.04 LiveCD and install on the same partition where your current Ubuntu is installed. During the install the partition will be re-formatted and GRUB re-installed, leaving no trace of your old installation.

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Thank you! i will try this – user772401 May 3 '12 at 1:12

There are some free (and legal) boot repair disks here:

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Thanks this is good help! – user772401 May 3 '12 at 1:12

I don't think that you need to re-install the MBR, but what you do need to do, is boot into windows (you can still do that right), and then delete your Ubuntu partitions, then from there you will be able to install Ubuntu 12.04.

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  1. As your Ubuntu 11.10 system is broken, you can repair and upgrade it to 12.04 by booting on a 12.04 CD or USB, then install it above 11.10 via this method: This will preserve your software configuration (/home).
  2. If you really want to uninstall Ubuntu (or whatever OS), you can use OS-Uninstaller
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You can boot up with an Ubuntu live USB or CD and use the following command in a terminal window to fix the MBR.

dd if=/usr/lib/syslinux/mbr/mbr.bin of=/dev/sda
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