Mostly due to plugins or Themes, Rename your plugins or Theme folder to "plugins.bak" or "Themes.bak" and try again.
Error establishing database connection
This means that there is a problem with the connection to your database.
Major causes
Incorrect wp-config.php Information
Open up wp-config.php and ensure that the following are correct:
- Database name
- Database username
- Database password
- Database host
