It might be necessary to deactivate all plugins when you are having issues with the website or issues reaching wp-admin. To do this, there are two simple ways:

 

Use phpMyAdmin to deactivate all plugins:

  1. Log in to phpMyAdmin
  2. Select the database
  3. In the "wp_options" table, in the column "option_name", look for "active_plugins"
  4. Change the "option_value" to: a:0:{}


Or use SFTP:

  1. Log in via SFTP, and go to the wordpress/wp-content/ folder
  2. Rename the "plugins" folder to "plugins.hold"
  3. Now log in to the wp-admin of your website
  4. Once you are logged in, rename the folder to "plugins" again