Troubleshooting a 500 error

SYSTEM INFORMATION
OS type and version Debian Linux 12
Virtualmin version 7.30.4

I’m setting up a new website and seeing some 500 errors. Unfortunately, the developer is unresponsive (it’s Sendy) so I’m trying to do what I can to find the problem. The apache error log in the Virtualmin dashboard is not showing any errors related to this site. I can see a few access lines in the Virtual Server / Logs and Reports / Apache Access Log when I try to load a page, but they just look like logs of access info to me (I’ve posted an example below).

Where should I look to try and track down more info?

192.168.1.1 - - [11/Feb/2025:14:45:47 -0600] “GET /favicon.ico HTTP/1.1” 404 397 “http://sendy.transactiontek.com/sendy” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36”
192.168.1.1 - - [11/Feb/2025:14:45:47 -0600] “GET /sendy HTTP/1.1” 500 707 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36”
192.168.1.1 - - [11/Feb/2025:14:45:34 -0600] “GET /sendy/login HTTP/2.0” 500 613 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36”
192.168.1.1 - - [11/Feb/2025:14:45:26 -0600] “GET /sendy/ HTTP/2.0” 500 613 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36”

Just to be clear, you are looking under the affected virtual server?

Apache should keep its’ own log but I’m not sure where that would be if you aren’t using rsylog. You can try filtering on apache here. Say 1000 lines and use the filter apache.

I guess this software Get Started with Sendy
It look like a pretty simple setup.
make sure the APP_PATH is correct and maybe look for a debug line to uncomment or change in the config file like whats in wordpress, else you need a support forum or there support.

I found this on that error