truth's questions

I am trying to upgrade from 22.04 LTS to 24.04 LTS. I am having this problem:

It says:

Error during update

A problem occurred during the update. This is usually some sort of network problem, please check your network connection and retry.

But I don't have any problems with my internet. And I tried both Ethernet and Wi-Fi, and neither works.

I click on "Upgrade Now" button, then it successfully downloads stuff for a while, and then it gets stuck and throws this error.

Then I see this for a moment:

And then it all closes.

Other problems also exist. But I found the solution nowhere.

One thing to note here: package upgrades are working from terminal, but GUI upgrading is buggy for some days.

This is what I get after running sudo apt upgrade:

The following packages have been kept back: python3-update-manager update-manager update-manager-core 0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.

The above message is to provide context only, and it's not the question. It might still be relevant.

How do I solve this problem and upgrade to 24.04 LTS?

I have about 2 TB of image data which I want to group into .zip files. The sizes of individual files vary.

I want to put all these files into ZIP archives. Any .zip file cannot exceed 2 GB (1.8 GB for safety) after compression. How many .zip files I make is not a concern.

How can I accomplish this? The key task here, I think, is to figure out how many files of varying sizes can be put into a ZIP archive so that the archive doesn't exceed 2 GB in size without compressing them. And, of course, the whole process has to be automated. I cannot work through about 80,000 pictures manually.

Please suggest ways to achieve this.