Deactivate WordPress plugin after 500 Internal Server Error

This is not an expert article.
The goal of this article is to share my experiences related to problems and challenges I have had on my computer environment. I hope it can help people who are struggling with the same issues.

As a beginner of WordPress I set up a multi-site network with multiple domains and started my first post. Next I started installing some plugins to play around. The first plugins worked fine. However, when I installed the next plugin something went wrong. I noticed that I could still open the dashboard of the site I was working on, but I was not able to enter the Network Admin area to manage the WordPress Network. I got  a HTTP 500 Internal Server Error. On the internet I found the following link:

http://www.wpbeginner.com/wp-tutorials/how-to-fix-the-internal-server-error-in-wordpress/

Here it is explained that there could be several causes for this problem. Plugins could be one of the causes. If this is the  case then the plugin must be deactivated. The problem now is that due to the HTTP 500 Error I was unable to open the network plugins menu to disable the latest plugin that was installed. Then I found the following link:

http://www.wpbeginner.com/plugins/how-to-deactivate-all-plugins-when-not-able-to-access-wp-admin/

This article explains that all plugins can be deactivated by renaming the “../wp-content/plugins” map into a different name . Renaming can be done using FTP, but I used SSH in my linux terminal. After remote login I changed directory to the wp-content directory and renamed the plugins directory using the following terminal commands on the server site:

cd WordPress/wp-content
mv plugins plugin_tmp

Next I tried to enter the WordPress Network Admin area again using my browser. It turned out now there was no HTTP 500 Error. Therefore is must be concluded that one of the plugins was causing the problem. Next I renamed the plugins directory to its original name and started looking for the specific plugin that was causing the problem. This was done by  renaming one of the plugin sub-directories to deactivate a specific plugin. This way I could determine which plugin(s) were causing the problem and which not. I removed the problem causing plugins using the terminal commands:

cd WordPress/wp-content/plugins
rm -R plugin_name

where “plugin_name” was the directory name of the plugin to be removed. This procedure has solved my  HTTP 500 Internal Server Error on entering the WordPress Network Admin area.