What to do when WordPress site crash

Firstly, I would like to emphasis the importance of keeping backup of your wordpress website incase you need to restore it. You can read it here under section 15.

WordPress usually breaks down when you install or update a new theme or plugins that has code error. First locate what the cause may be by knowing what you last did that cause the crash. You can also check if it is caused by theme or plugins by restoring back to its default mood. This can be done by renaming the folders or file in the cPanel under File Manager.

For instance, if renaming the theme folder does not fix the wordpress, then the cause most likely to be in the plugin folders. You can rename the theme folder back to it’s original name. Then rename the plugins folders. If the website is back on or is blank, it means the problem is due to the plugins. You can change the plugin folder back to it’s original name. The the last part is to identify which plugins has code error. I would start with the latest plugin that was installed or updated. Rename the folder and if the website is back on, it means that the plugin was the caused of the breakdown. To resolve this problem, you can update the plugin from the wordpress admin area or decide to delete the plugin all together.

If the code error is not from the theme or plugin folder, then you can go check each folder one by one through restoring it via renaming the file.  

How to restore your site.