Occasionally a site user or developer will navigate to a page and suddenly the page content disappears, and it becomes blank. No content. No errors. Nothing. This happens sometimes, It could happen after updating a module, theme, or Drupal core. This is what is referred to by most members of the Drupal community as the White Screen of Death or WSOD. There are several reasons why this might occur, and therefore several possible solutions to the issue.
(Note: The suggestions on this page might solve the problem even when you do not get the WSOD as it relates to an Internal Server Error.)
If error reporting is turned off, you could be getting a fatal error but not seeing it. On a production site, it is common to have error reporting turned off. If that is the case and PHP has hit an unrecoverable error, neither an error nor content will be displayed, therefore you end up with a completely blank page.
What you can do about this is either turn on PHP error reporting so it displays a message on the page itself, or check your log files (from the server) to look for the error. How to do both of these are explained below.
Enable Error Reporting