GRUB doesn't detect Windows an second hard drive

boot dual-boot grub2 windows xubuntu

7,334

I had the same problem, os-prober did not detect my installation either, it was because on my windows 7 partition there was files missing...

/grld
/Boot/BCD

Don't know the utility of these files but was missing... I copied them from other windows install and solved the problem

pg@pipoTower: ~$ sudo os-prober 
/dev/sda1:Windows 7 (loader):Windows:chain
/dev/sdc1:Windows 7 (loader):Windows1:chain
/dev/mapper/lvmvolumeSda6-root:Ubuntu 15.04 (15.04):Ubuntu:linux

Possible duplicate

GRUB does not detect Windows

7,334

John Scott

Updated on September 18, 2022

Comments

John Scott almost 2 years

I helped a friend of mine dual-boot Xubuntu 14.04 and Windows 7 Professional. I put WIndows 7 on a 80GB hard drive and put Xubuntu on a 1TB drive. I booted into Xubuntu and ran update-grub, but it didn't detect Windows. I tried doing it with the drive mounted and unmounted. Also, the system uses BIOS, not UEFI. It is a fresh Windows 7 installation so it is by no means fragmented or damaged and I fully shut down the system. What do I do now?
- vembutech over 9 years
  
  It might be due to the permission issue, so please use sudo chmod 755 /etc/grub.d/40_custom and then reboot the machine. Hope this will help you to fix the issue.
- Fabby over 9 years
  
  Did you use the BIOS to change the boot order when installing to the 1TB drive? (grub only installed on the 1TB so doesn't detect the windows on the 80G)
- John Scott over 9 years
  
  @Fabby Change the boot order to what? The computer is set to boot from the 1TB drive with Xubuntu and doesn't detect Windows. Running sudo update-grub shows that it doesn't detect Windows at all, with the drives mounted and unmounted. UPDATE: I think the problem was that Windows was installing updates or hibernating so it couldn't be detected. How do I boot into Windows to correct the problems? (The BIOS only gives an option to boot from hard drive, but won't let me choose a specific drive, and just boots to the 1TB one.)
- John Scott over 9 years
  
  It turns out that I had installed Windows incorrectly. I reinstalled and the dual-boot works good now. We can close this.