Check & test your mail server, from v4.2 php mailer was upgraded from 5.x to 6.x
@alex7070No, PHP mailer is upgraded to latest version, there are some differences so you should check your mail server configuration and test it.
@alex7070I would suggest using Test button in Settings > Mail server
Well you have nothing there so you did nothing yet.Fill all information with data from hosting provider, regarding mail server.
@alex7070Usually, when you use php send mail, that mail goes to spam folder.Osclass use PHP mailer library and not php built-in mail function.You can get all those information from hosting provider, I think I mentioned that at least 2 times.