Ubuntu upgraded to 24.04 from 22.10, now getting grub message "Symbol ‘grub disk native sectors’ not found"

I have seen several questions about the same issue but they are either not answered or the answer is not relevant as it is about a different Linux variant When performing the upgrade, towards the end of the process, I kept getting a message about something not responding and waited 5 or 6 times before I thought it best to force it to stop. After the restart I got the message in the title. I have downloaded the boot repair disk and run it several times but it didn't work. I generated a report on pastebin at https://paste.ubuntu.com/pRD5n4vPvp This is an old system with MBR/msdos partitions on the boot disk. I don't have a USB stick of more than 4GB that I can use and I also can burn an ISO on my windows system if I need to - but 24.04 iso is about 6GB.