Re: Installing ubuntu on separate disk makes windows stop booting
You need to have the following:
1) GRUB installed to the Ubuntu drive, NOT to the Windows drive
2) Windows drive disconnected when you install, or reinstall GRUB
3) Booting from the Ubuntu drive, not the Windows drive
Having the Windows drive connected resulted in GRUB being installed to THAT drive, not to the Ubuntu drive. Furthermore, depending on how Win7 boots, that can hose up the Windows booting in the process.
Since you have Windows installation media, do the following:
1) Disconnect the Ubuntu drive
2) Boot from your Windows DVD and choose Repair Install. Do that three times. Confirm that Windows boot from that drive.
3) Disconnect the Windows drive, connect the Ubuntu drive, boot from your installation media
4) Install GRUB to the Ubuntu drive -- see: http://ubuntuforums.org/showthread.php?t=224351
5) Reboot, confirming that Ubuntu now boots OK
6) Shutdown, reconnect the Windows drive -- but continue to boot from the Ubuntu drive
7) Boot into Ubuntu, once there, open a terminal and enter "sudo update-grub". This will regenerate the GRUB config file and you should see it detect the Windows 87 Loader.
8) When you reboot now, you should get a GRUB menu with entries for Ubuntu and Windows 7.
Ubuntu 16.04 Mate, Mint 18 Mate; MS Win 8.1, MS Win10 Pro.
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