PHP script that sends emails does not work. The following error can be found in mail log on Linux:
MAIL MAIL FROM:<@adminemail@> SIZE=359 555 5.5.2 Syntax error.
In MailEnable SMTP Activity log on Windows:
06/06/16 16:17:33 SMTP-IN F4263D896EF14A7EA44A0DB04E4D55FE.MAI 956 127.0.0.1 MAIL MAIL FROM:<@adminemail@> 250 Requested mail action okay, completed 43 26
Check what PHP version is used by domain in Domains > example.com > Hosting Settings > PHP, and which configuration file is used for this PHP in Domains > example.com > PHP Settings > php(info).
Connect to the server via SSH/RPD and open corresponding PHP configuration file, for example:
C:\Program Files (x86)\Parallels\Plesk\Additional\PHP56\php.ini
Open php.ini and find these lines:
SMTP = localhost
smtp_port = 25
sendmail_from = @adminemail@
Correct sendmail_from to valid email address like:
sendmail_from = email@example.com