If you’re experiencing problems with your website, e.g. a white page is displaying instead of your website, then you can check your WordPress log file for exact information on the problem. The location of the error log is in the root directory and it’s a file called error_log that records php errors.
For example an error on a website we were troubleshooting this morning gave us the following information which pinpointed a problem in the site configuration file:
[01-Jul-2014 10:47:35 Europe/London] PHP Parse error: syntax error, unexpected ”WP_CACHE’, true); // Added b’ (T_ENCAPSED_AND_WHITESPACE), expecting identifier (T_STRING) in /home/diamondb/public_html/wp-config.php on line 3