I bought my first computer in 1980 in Halifax, Nova Scotia. It had a Z80 at 4 MHz, 64K of RAM and two 8-inch floppy disks of 600K Bytes.
I bought my current laptop in 2018. It came with Windows 10. On it I installed Linux, more specifically Ubuntu 18.04 LTS (Long-Term Support).
For the last 6 years, I did not upgrade this version of Ubuntu.
Recently, I was getting hints that it was time to upgrade, as some apps were threatening to stop working on Ubuntu 18.04.
To upgrade, I needed to do it in three steps: first to 20.04, then to 22.04, and finally to 24.04.
Before upgrading, I saved most of my files on a 128 GB USB flash drive, that I bought at Walmart for CAD$25. Incidentally, I bought my first USB flash drive in Beijing some 20 years ago: it had a capacity of 250 MB and I am sure that it cost me more than $25.
So, I first upgraded to Ubuntu 20.04 LTS with no problem in less than two hours, with no problem.
From 20.04, I upgraded to 22.04: again I had no problem.
However, when I upgraded to 24.04 LTS, I was no longer able to boot any version of Ubuntu because of corruption in the booting process.
Fortunately, I could still boot Windows 10.
As I had not updated Windows for some times, I had to spend several hours to update it, with several restarts of my computer.
Then, I was able to download Ubuntu 20.04.LTS and put it on another 128 GB USB flash drive as an ISO file.
I had to find the way for my laptop to boot directly from the flash drive. There is no standard way to do it for different brands of computer.
Finally, I was able to boot from the flash drive and to install Ubuntu 24.04 LTS on my six year old laptop.
