Contact Form Processing Products - for all your needs

FormMail • Form Encryption • Hosted Forms


This page documents the SENDMAIL_F_OPTION configuration setting in FormMail.

Type Of Setting

SENDMAIL_F_OPTION is a LEAVE setting, which means...

LEAVE : you can change this setting if you really need to and know what you're doing, but we recommend that you leave this setting unchanged.


Controls use of "-f" option for sendmail.


SENDMAIL_F_OPTION controls whether to use the "-f" option when sending mail.

Some servers use a Mail Transfer Agent called "sendmail" and some of these require the "-f" option to be provided - this option tells sendmail the "From" user or sender.

FormMail originally supported this feature using the "mail_options" setting inside your HTML forms. That was a silly place for us to put this feature! It's a server configuration, so it should live in the configuration section of FormMail, not in your forms.

Set SENDMAIL_F_OPTION to true to tell FormMail to specify the "-f" option when sending mail or set it to false to prevent FormMail from specifying it.

Review the email logic description for more information.

Default Value

From version 9 onwards:


Before version 9:



From version 9 onwards:


Before version 9:


See Also