HTTP ERROR 500 after my host upgraded to PHP 7.2.14

By Mariann Davis
February 15, 2019, 6:31 pm EST

Although my site displays fine for visitors, I cannot login to my WordPress dashboard ever since my host upgraded from PHP 5.6 to 7.2 two days ago.

I get the login screen but then i get

This page isn’t working
uucsjs.org is currently unable to handle this request.
HTTP ERROR 500

So i cannot get to the dashboard to check on anything.

Important note: 

On this same host, i have a subdomain, members.uucsjs.org, that also uses Wordpress but a different theme, and an older version of Wordpress (4.9.9), which i can get to the dashboard just fine.

So I'm deducing that it's the uua theme that is the issue?
I have the older version of the uua theme (because there were some problems when it first came out and i was waiting for enough time to pass).
How do i fix this?

Mariann Maene
uucsjs.org 
South Jersey Shore

Comments (2)

Scorpia22 replied:

I disabled plugins and the dashboard came up. I re-enabled plugins and, after activating WP_DEBUG, the site comes up but with a failing plugin: List Category Posts. The error was something like invalid index on Pagination. I wasn't using the Pagination, but i set it to yes and the error went away; I set it back to No and the error didn't come back. So some kind of initialization error for that plugin? Anyway, seems fixed now.

The error is too generic and does not tell you exact problem. What you need is to find out what is the real issue. If your site is serving a Internal Server Error, this can be caused by a number of things, such as:

  • Server permission
  • Server timeout
  • Script timeout
  • Errors in .htaccess files
  • Exceeded PHP memory limit.
  • Or some other Web Server Issues

Normally, a permissions issue on the file (or files) would be one cause of the 500 Internal Server Error. The simple solution is to run chmod 644 on the problem file(s) or chmod 755 on the directories.

$ sudo chmod -R 777 /"your files location"

The best way to debug the error depends upon the server and what’s actually running at the time. Consider some debugging tips to help diagnose and fix common causes of this problem.