I had a multi boot setup with Ubuntu 15.10 for a couple of years with no problems, but after upgrading to Ubuntu 18.04, I get the GRUB prompt when trying to boot Ubuntu.
I have Windows 7 and Windows 10 on Disk 0 and Windows XP and Ubuntu on Disk 1. Both disks are BIOS setups (non-UEFI). I installed Ubuntu 18.04 (and GRUB2) on Disk 1, Partition 2. I can boot from either Disk 0 or Disk 1 (as selected in the BIOS). Disk 0 is set up with 4 boot entries (Win 7, Win 10, Win XP, and Ubuntu). From Disk 0, all three Window options work as they always did, but selecting Ubuntu takes me to the GRUB prompt. Disk 1 is set up with 2 boot entries (Ubuntu and Win XP). From Disk 1, Win XP boots fine as it always did, but selecting Ubuntu takes me to the GRUB prompt. Note that I deleted the original Ubuntu entry on both Disks and then added it.
The next thing I did was to boot from a Live Ubuntu CD and updated the MBR on Disk1 to point to the GRUB bootloader on Disk 1, Part 2. When booting from Disk 1, the GRUB menu now comes up with the GRUB menu. I can get to the bootloader (with all 4 options) on Disk 0, the Win XP OS on DIsk 1, Part 1, and Ubuntu on Disk 1, Part 2. These all work fine from the GRUB menu. If select the bootloader on Disk 0 and then select Ubuntu, it goes to the GRUB prompt.
I have seen some other folks complaining about getting to the GRUB prompt after updating to a newer version of LINUX, so I don't think the problem is specific to something in my particular setup.
Any help would be appreciated.
I have Windows 7 and Windows 10 on Disk 0 and Windows XP and Ubuntu on Disk 1. Both disks are BIOS setups (non-UEFI). I installed Ubuntu 18.04 (and GRUB2) on Disk 1, Partition 2. I can boot from either Disk 0 or Disk 1 (as selected in the BIOS). Disk 0 is set up with 4 boot entries (Win 7, Win 10, Win XP, and Ubuntu). From Disk 0, all three Window options work as they always did, but selecting Ubuntu takes me to the GRUB prompt. Disk 1 is set up with 2 boot entries (Ubuntu and Win XP). From Disk 1, Win XP boots fine as it always did, but selecting Ubuntu takes me to the GRUB prompt. Note that I deleted the original Ubuntu entry on both Disks and then added it.
The next thing I did was to boot from a Live Ubuntu CD and updated the MBR on Disk1 to point to the GRUB bootloader on Disk 1, Part 2. When booting from Disk 1, the GRUB menu now comes up with the GRUB menu. I can get to the bootloader (with all 4 options) on Disk 0, the Win XP OS on DIsk 1, Part 1, and Ubuntu on Disk 1, Part 2. These all work fine from the GRUB menu. If select the bootloader on Disk 0 and then select Ubuntu, it goes to the GRUB prompt.
I have seen some other folks complaining about getting to the GRUB prompt after updating to a newer version of LINUX, so I don't think the problem is specific to something in my particular setup.
Any help would be appreciated.