Looks like that version doesn't like PHP 5.4. I was able to fix the server 500 errors and get the site to display, but now I'm getting MySQL errors which I'm told is due to the difference between PHP 5.3 and 5.4.
[12-Aug-2021 23:13:47 UTC] PHP Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in /home/mywebsite/public_html/ubbthreads/mysql.inc.php on line 139
If I could just get the DB connection to work I could probably just run the upgrade even if there are conflicts with PHP. Otherwise it looks like I'll have to copy it all to a server where I can install PHP 5.3.
