kstan

I see... Well, I am my own hosting provider (although I don't really know what I'm doing), and I did in fact have ModSecurity installed. It seemed like a difficult and risky task to just turn it off altogether, so instead I experimented with turning certain features off, and lo and behold, turning off "Backend Compression" did the trick! Thank you for saving me!

Would that be in the conf_global file? Is so, I do not.

When I click the "Edit HTML and CSS" button for a theme (any theme) I get an "Internal server error". I have tried to look for information in the error log for the server, but I can't find anything. I also tried to downgrade to PHP 8 from PHP 8.1, but that makes the whole site fail. I also tried to disable plugins to no avail. I have no idea what to do next.

I just want to report that the problem has finally been resolved. In the end converting the database to utf8mb4 did the trick. I can't find it now, but I think someone at some point asked me why I hadn't done that. I replied that I intended to, but I wanted the other problem resolved first before messing with converting the database. Nowhere that I saw was utf8mb4 listed as a requirement to upgrade, but nonetheless, that's what solved it. Thank you to everybody who tried to help. Much appreciated!

It appears to be running without errors. Everything seems fine except that it won't update. As far as a backup, since the problem first started in July, I no longer have a backup that old. What I would be interested in knowing is if it actually performed those changes to the database to make it ready for 4.7. If so, would it be possible to install IC 4.7.3 from scratch with a new database and then, after installation, connect it to the old database?

Hmm.... I see what you mean. When you asked your question, I went to my dashboard to check, and my dashboard says I have 4.7.0, so that's what I replied. However, the upgrade to 4.7.0 never finished succesfully, which is the whole problem. Another detail is that the upgrade I'm trying to perform says it includes version 4.7.0 through 4.7.3. So I probably still have 4.6.12.1, but my dashboard thinks I have 4.7.0. Or something. I'm confused.

4.7.0

Thank you for the suggestion. I now tried to roll back from PHP 8 to 7.4, but unfortunately, it made no difference. I still go around in circles.

I also used Navicat for MySQL which is a desktop app. It did take a few minutes, but it performed all the commands without error.

Does phpmyadmin or similar MySQL software qualify as SSH? Because I did that and the result was the same.

It's too long to post, but I attached it. query.txt

One week later... The database no longer crashes when I attempt the upgrade. It still tells me there is a problem with the database and to run a long query before proceding with the upgrade. I do that. It goes fine, no errors, but after finishing the query, it once again tells me there is a problem with the database and to run the same script again. In other words, I'm going around in circles and never get to the point where I can do the actual upgrade. Any ideas?

Okay, I will do a thorough database check and see what else I can do on the server side.

Failed again. I'm getting "Incorrect key file for table..." error messages for different tables when I try to load the forum. I try to repair tables, but they are unrepairable. Now trying to reestablish the database from a backup. Any ideas?

Thank you! I did not know that. I will try the update again and hope for the best.