Server 500 error in a View which is working perfectly outside of the admin area I have a View which is affected by several hooks ( views_pre_viewand views_query_alter, mainly). It works perfectly in the final user area, but when I am logged and go to the Views GUI, the browser displays the following error message:

 An AJAX HTTP error occurred. 
 HTTP Result Code: 500
 Debugging information follows.
 Path: en/admin/structure/views/view/NAME_OF_VIEW/preview/block/ajax
 StatusText: Internal Server Error
 ResponseText:


I see no error loging in the recent log messages, the browser keeps working, I can modify the View, but I am worried that something may broke later in the final user area. How can I debug what is happening? I have no previous experience in Devel or similar.
You are going to have to access the PHP error log file to determine the cause. Drupal may not always log an error since it the error may stop it from running. I would contact your host to see if they can provide you the log.