eForm:: ERROR

Hello,
I have a little contact form but when I submit it I have and error,
the error is: "Main mail: Mailer was unable to send mailCould not instantiate mail function. "
I already saw the examplesof the modx and I don’t know what I did wrong...
Please you could explain me what means this error and what do I do for the form submited correctly

Thank you

This message means your PHP installation does not have access to a sendmail program on the server. It’s not a MODx problem. In fact, if you got this far, your form worked and is trying to send the email.
You need to check with your host if sendmail is supposed to be available to you, and check the PHP configuration if it should be. (Look in the MODx Manager > Reports > System Info > PHPinfo() -> View, see what it gives as sendmail_path)
KP

Thank you for your help
I already resolved the problem with the apache server