Funny thing happened with Drupal 7.50, errors started appearing that I had no clue about. It started telling me about modules not being where they were supposed to be and about a utf-8 not being enabled.
One of the errors received was:
The following module is missing from the file system: <em class="placeholder">plup</em>. In order to fix this, put the module back in its original location. For more information, see <a href="https://www.drupal.org/node/2487215">the documentation page</a>. bootstrap.inc:1128.
I was immediately frustrated by this. All I wished to do was a "simple" upgrade and I'm getting hit with problems. I abandoned what I was doing and went into hiding. I have been doing drupal for coming on my 3rd year, and it seems like every time I feel like I'm starting to get the hang of things something happens and it makes me feel like I'm back to being a beginner.
Don't get me wrong, I'm learning lots, and I'm a great deal farther along than I was even 8 months ago, but sometimes it would be nice if I had a chance to choose what I have to learn next instead of having to respond to the next change in the software.
It has been a couple of months since 7.50 came out and I am finally to the point where it is sinking in.
The file issues were because they have "tightened down" the database and the module relationship. In the past there was no check and balances with modules. In modules you have enable and disable. There was also uninstall. I did not have much of an understanding of what the 3 meant in Drupal. If you wanted to install a module all you had to do was download it and enable it. If you wanted to stop using it all you had to do is disable it.
I saw the uninstall tab and that was where the disabled modules would be listed. When you click uninstall it would remove the entries in the database, but it would leave the module and that was it. If you deleted the module it would no longer appear in the uninstall tab, so what happened? I'd delete the module and not bother uninstalling it.
Enter Drupal 7.50, now when you do any drush command you get an error message that modules are missing (the modules that I deleted without removing them in the database). Damn! I tried to figure out how to get rid of those error messages. Going to drupal.org or doing google searches were not much help with finding a simple solution, one that a still inexperienced Drupaler could figure out.
It took me a week or so but I finally concluded the easiest thing to do would be to write down each module that showed up in the error messages, download them again onto the site, go into modules/uninstall and uninstall them, then go back and delete the modules. That did it. My head was spinning at some of the other "fixes" I was finding, things like going into the database and running MySQL Commands, things that could easily escalate one's problems. Nope, re-downloading the modules was definitely the safest thing to do for this issue.
I'll cover the UTF-8 issue next time.