Hey, I got that message too. LOL Do you have any theme reset plugins? This is how I fixed mine.
1) install Advanced reset wp.
It is important to do this as I tell you too so you lose nothing concerning your posts or pages.
2) Do you have a child theme for the current theme that backs up your customizations? There are plugins that do this. Download one and make one if you do not have a child theme. This is the best child theme creator. It also allows you to backup up your themes and their customizations.
3) Backup everything. Make a separate backup of the data base. And for insurance download the full backup to your pc and the separate database backup. This is just for insurance if something really bad happens. But I have done this several times now nothing bad happened. But it’s better to be safe than sorry. Make a list of the names of all your plugins. You will be installing them manually.
If you do not use the child theme creator to backup themes. Backup your themes separate from the other backups. You can either do that from a FTP program, or if you happen to have access to the server control panel for your website usually known as Cpanel. You can download in in the files section. If your installation is in the root directory, the location of your themes will be: wp-content/themes/”a list of your themes”
4) Uninstall all plugins manually aka one by one.
5) Using the “advance reset” found under tools in your admin panel use the deep cleaning option. The bigger the site the longer it takes to clean. If after 10 minutes the page does not refresh telling you it’s done, refresh the page yourself. It sometimes does not refresh page. You will find yourself logged out which is normal, just log back in.
Now you have a complete fresh install.
6) The full install is not needed right now so don’t worry about it. It’s for: if this procedure does not work you can quickly get site back up and running.
7) From your list of plugins only install the plugins you had before the problem started. Any paid for plugin would not do this. It’s one of the free ones. So you can install all the paid for ones regardless.
8) Install the theme you were using along with it’s child theme you created.
9) Restore data base from the separate data base backup you made. Do not restore directory just database. That is where the problem is and you will put it back in if you do this.
10) Check your site to make sure it’s up and running again.
11) Check for the problem. Should be gone.
12) Install “wp clean fix”. Run all the cleaning options except for any posts or pages you want to keep backups of. The clean install of everything will enable this plugin to better find what should not be there in your database you just restored and give you the options to remove it or not. Read any warning that may pop up during a cleaning to make sure you are not cleaning something where you will lose something. If you do by accident all you need to do here is one thing to get it back Restore Data base and everything you just cleaned with this plugin is back in again.
This plugins just deals with the data base, nothing else. So data base restore fixes anything that this plugin does you did not like. And that is just a one step procedure.
Now why do it this way? 2 things.
1) You are removing everything that any other plugin may have left behind. Not everything is removed when you delete plugins. Some plugins leave things. And if you do a lot of experimenting like I do, you are constantly trying new things until you find what you want. This procedure in removing all the left behind stuff will speed up your site a little and make it more stable and smooth loading.
2) When you install everything manually minus the plugins that were recent around the time of the problem. You are actually installing what was in the directory but a fresh install of directory. Same thing goes for the themes. They will be fresh installs as well.
Doing it this way cleans up your code too. Some plugins leave stuff in your codes files and headers in different places on your website. This procedure will clean that out.
**Note keep the old backup that had the problems for a few weeks just to be sure. Backup everything with the fresh install (after this fix) before you do any changes and make a note that this is the fresh install backup. If everything works out, delete and replace with new backup. This way you never accidentally put the problem backup back in and end up having to do all this again.