Newly installed 20.04 not showing up in boot list

I have a dual-boot laptop with winxp and ubuntu 18.04 32 bit installed. Now I am trying to upgrade my machine to 20.04 64bit version.

Instead of overwriting 18.04, I installed ubuntu 20.04 on a third partition. During installation, when asked to specify boot partition, I selected the old partition where /boot was mounted.

The installation was a breeze. But after restart I still see only the old options in boot list: ubuntu 18.04 and winxp. Even the Advanced options shows the same two 18.04 kernel versions as before. After booting in 18.04, I mounted the partition where 20.04 is installed and I can see all the files there. But I'm not able to boot into it.

Any clues how I can get 20.04 to be visible in GRUB? Was my selection of boot partition wrong?

Solution 1:

open terminal and run:

$ sudo update-grub