My Personal Technical Resource
Stuck at the grub prompt after upgrading a kernel?
If you get stuck at the grub> prompt after upgrading a kernel you might be able to fix it easily. This tutorial applies to Debian and Debian based distributions, such as Ubuntu or Linux Mint.
I have had this happen to me a few times after a kernel upgrade is downloaded and installed with the usual updates. For some reason update-grub does not seem to get called or it does not complete successfully.
This tutorial assumes that you are booting off the primary hard drive and using the default partitioning layout on a system with only Linux installed. You may need to modify the parameters to match your specific configuration.
First try to see if you can get to the grub boot menu.
If you get the boot menu, then you are in good shape. Go ahead and choose the latest kernel and boot the operating system. If not, then you should troubleshoot the specific error until you can successfully repair grub or at least get to the grub prompt.
Next, after you boot the operating system, you want to open up a terminal session and type the following:
$ sudo update-grub
After that, reboot and see if the grub boot loader comes up again.