There are many possible reasons for this problem (White Page of Death, you can search for it).
I'm listing here some major ones, and not it great detail. For details you can go to the links mentioned at the end.
Plugins cause problems mainly after an upgrade, or if you've installed obsolete versions of the plugins. One way to quickly check to see if one of your plugins is problematic is to do the following:
- Rename “plugins” folder temporarily to something else.
Wordpress will automatically disable all the plugins.
- Enable all your plugins at once
Wordpress will enable only those plugins that don't crash and will disable any plugins that produce fatal errors.
- Enable plugins one at a time
Alternatively, you can enable one plugin at a time and observe which one leads to the crash.
Once you identify the problematic plugin or plugins, see if they have been updated. If they have, delete the ones on your server and replace with the newer versions. Hopefully that will work. Otherwise, just leave the bad plugins de-activated until they are updated.
2. Empty Line in `wp-config.php` file
Make sure the the file is in Wordpress directory, has correct DB information and doesn't contain any extra lines after the closing