The most common issue mentioned in the forums is that an application comes up with a blank white screen in the web browser. This can happen for a number of reasons but the most common reason is because PHP has encountered a fatal error and your PHP installation is not set up to display errors.
The first step to troubleshooting this problem must be to find out what the error is. You can do that in one of the following ways:
Check your Apache error log if you know where it is. One common location on many linux installations is
but your system may have it located elsewhere. If you cannot find your error log, continue to the next option.
Turn on the display_errors flag in your php.ini file. I.e., in your php.ini file, find where it says
and change it to
. After this is done, restart your apache webserver. If you don't know where your php.ini file is located see the section later in this document on locating your php.ini file. If you don't have access to your php.ini file, move on to the next option.
In your application's .htaccess file, add the following directives to enable displaying errors:
php_flag display_errors on
. Note that this method will only work if your apache config file allows you to override these values at the directory level. If you still get a blank white screen after this, continue to the next option.
At the beginning of your application's index.php file, add the following: