Having the same problem here.
The php-error logfile shows these errors:
Code:[23-Jan-2024 22:00:43 Europe/Amsterdam] PHP Notice: Undefined index: 2023/12 in C:\inetpub\wwwroot\stat\plugins\mail\mail.php on line 5
[23-Jan-2024 22:00:45 Europe/Amsterdam] PHP Warning: mail(): Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set() in C:\inetpub\wwwroot\stat\plugins\mail\mail.php on line 5
When I use the mailserver address of my mailprovider I see an error in the log that states I need to enter my credentials. Here I'm lost. Where do I do that?