Blank white pages is a PHP error. For some reason(s), the typical error message doesn’t show up because your server is not configured to display the error(s). While 500 Internal Server Error means something has gone wrong at server end but it is unable to specifically state what the exact problem is.
The similarity between both issues is that it doesn’t give us a clue what exactly has happened, or which files are triggering the errors. So, the first step, before we try to solve the errors, would be to try to show up the error messages. Then use the error message as a reference to investigate what is causing the error. Here are a few ways to show up error messages:
- Set your “Output Compression Level” to 0 in the System > Settings > Server tab.
- Then open php.ini and add code below:
display_errors = 1;
error_reporting = E_ALL;
log_errors = 1;
- If you can not access php.ini, use an alternative method. Open index.php and add the code below at the top (line 2):
When you have fixed the problem, remove code line above.