500 Error

[mjherm]

I upgraded to 8.0.0 (and 8.0.1) and when I try switching from PHP 7.3.23 to PHP 7.4.11 I get a "500 Internal Server Error" whenever I browse to the client facing or admin pages of WHMCS. The PHP.ini of both versions are identical.  Anyone have similar issues and how did you resolve? I tried both Apache and nginx.

 

2020-10-06 15:13:32	Error	72.92.39.41	502	GET /adminpanel/index.php HTTP/2.0			552	nginx SSL/TLS access
2020-10-06 15:13:32	Error	72.92.39.41		1808168#0: *2518828 recv() failed (104: Connection reset by peer) while reading response header from upstream				nginx error
2020-10-06 15:13:35	Error	72.92.39.41	502	GET /adminpanel/index.php HTTP/2.0			552	nginx SSL/TLS access
2020-10-06 15:13:35	Error	72.92.39.41		1808168#0: *2518828 recv() failed (104: Connection reset by peer) while reading response header from upstream				nginx error
2020-10-06 15:14:01	Error	72.92.39.41	502	GET /adminpanel/index.php HTTP/2.0			552	nginx SSL/TLS access
2020-10-06 15:14:01	Error	72.92.39.41		1808168#0: *2518828 recv() failed (104: Connection reset by peer) while reading response header from upstream				nginx error
2020-10-06 15:14:37	Error	72.92.39.41	500	GET /adminpanel/index.php HTTP/1.0			3.84 K	Apache SSL/TLS access
2020-10-06 15:14:37	Warning	72.92.39.41		(104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server				Apache error
2020-10-06 15:14:37	Error	72.92.39.41		End of script output before headers: index.php