In the manuals are listed a smtpmail plugin , but I can't find this plugin is this deleted, I am in need for this plugin . Can anybody upload this plugin again for me .
I don't know there is a plugin which gives you possibility to sending emails using SMTP connection but if you need this feature you should add PHPMailer library into your project and modify sendEmail() function in core/common.php. If you need assistance with this modification you can contact with me (info@marcinmorcinek.pl) and I will try to help.
It was not "plugin". It was special instruction (PHPMailer) visible only for OpenSolution partners https://opensolution.org/partnerzy-opensolution.html
If you want to do it yourself please check this link https://github.com/PHPMailer/PHPMailer/tree/master/examples