Limit on number of scripts running simultaneously in a page

[magikstm]

Try to add this line in your caddyfile to start php-cgi alongside caddy (instead of using a service):
on startup C:\path\to\php\php-cgi.exe -b 9123 &

Ref:

Easiest way to get PHP working with Caddy on Windows

I run Caddy with PHP over fastcgi very successfully on windows (despite @matt comments about people running webservers on windows ) A basic example is here The important thing to do is startup the php fastcgi server as part of your caddyfile. There is one other gotcha which is a php fastcgi issue not a Caddy issue and that is you must restart php fastcgi reguarily to prevent memory leaks. In effect this means restarting caddy if you are using the startup directive to start php fastcg…

https://caddyserver.com/docs/on

Which version of Windows are you using?