Ever since 3.9.1, WordPress has become unusable

No, I activated & tested the plugins one-by-one, but I didn’t activate them again in pairs in this “plugin dance” idea you pitched.

But so how would I recognize a plugin conflict if the same fault exists whether it’s the sole activated plugin, or when all the plugins are activated?

Oh – I am sorry! I may have mis-read one of your earlier posts. Just to clarify, do you only have problem X when plugin A is active?

That’s okay!

Yes I have problem(s) X when plugin A is active, problems Y when plugin B is active, etc.

After removing the plugins I didn’t need, the issue remaining with the plugin I do need is this:

When I delete the plugin and re-install it, it retrieves my old settings. I want it to be completely blank, as I think this will clear up the problem (because the same plugin works on my subdomain just fine). How do I clear all old settings from WordPress to ensure a brand new install when I re-upload it?

[ No bumping please. ]

That depends on the plugin. Some (but not many at all) remove their own data, most leave the data there in case they are used again, and some just don’t think/worry about it.

If the plugin that you’re looking at doesn’t remove it’s own data and you really want to remove it all, you’ll need to go through the database tables manually and delete anything that’s set by that plugin. The biggest issue with this is that even though you can look in the normal places, like the wp_options table, there’s no guarantee that it hasn’t left data in any of the other tables as well. On top of that, unless the plugin has used it’s own identifiable naming convention for it’s data, it’s going to be very hard to determine which values belong to the plugin and which are system entries.

Be careful with what you delete, and always keep a backup of the database before you make any changes, just in case something does go wrong.

Thanks, hmm that sounds impossible to do then. Is there anyway else to remove this remaining bug? Like I said, it works on the subdomain. Any JavaScript I can look for? I’m a technical caveman so if there is, I’d need you to tell me/point me to how to do it. Thanks.

The bug again, is that it isn’t uploading media files like photos.

And I’m still getting glitches in the basic WordPress interface. For one, I cant even center text with the WP page editor, even when all the plugins are turned off. How do I fix that?

How did this get so messed up, I don’t understand.

Have you actually asked the question to the plugins author yet? That advie was given a while back, and it’s still about the best chance that you’ve got of getting a good answer for what you are looking to do.

I will write to the plugin author about the plugin, that doesn’t explain why the WP itself is glitchy. I have had 3 separate people re-upload the WP files, one of who was my hosting company and two were hired workers. But the glitches in the WP itself are still there, separate from the plugins.

This issue is specific to your site. It is not a core WordPress problem.

Do you mean hosting? I spoke to my hosting and they ran checks and are adamant it is not them. What specific to my site do you mean? What could be causing things like I cant center text with the WP page editor even when all the plugins are turned off?

What specific to my site do you mean?

Your theme
Your plugins
Your server
The manner in which your site as updated

All of these are site specific factors.

Okay so I can deduct the first two:

The theme – The problem runs through all themes including 2011-2014.
The plugins – I turned them all off and still got the WP editor glitches.

Your server – By server, do you mean the hosting? I spoke to my hosting and they say it is not them. Or did you mean something else?

The manner in which your site as updated – What do you mean updated? The last major update was 3.9.1.

Can you replicate the problem using the default Twenty Fourteen theme with all plugins deactivated?

Yes, with 2014 and all plugins deactivated, I still can’t align text center or right.