PHP mail function call error

When specifying outgoing mail in site settings the parameter is automatically added to sendmail -fspecifying the name of the sender (field FROM). If site scripts try to override this parameter on their own, then when trying to send mail using the function mail an error may occur on the site of the impossibility of calling this function, like "Failed to call the mail function" or "Could not instantiate mail function" (the error text and the way of its output depends on the used CMS or framework). For example, this situation can be encountered when sending mail using the library PHPMailerwhich adds the parameter -f default.

To fix the situation, use one of the following methods:

  • Instead of the mailbox specified as outgoing mail, select "- Select e-mail -" (this will remove the parameter for sendmail -f):
  • Instead of PHP mail, use sendmail directly.
  • Use SMTP sending instead of PHP mail.