Individual forms can be corrupted, but I have never heard of that causing a problem with the notifications. Please see these troubleshooting tips for notifications: http://www.gravityhelp.com/documentation/page/Troubleshooting_Notifications
The issue in most cases is that the mail transfer agent on the host where the website is hosted does not want to deliver email which is pretending to be sent from some address. not on it's domain. For example, if you have a field in your form for the visitor to input their email, then you set up the notification to come from that address, you are telling the mail server to send email from some domain that is completely unrelated to the website domain. A lot of mail servers will fail to deliver email like that.
That's why using an external SMTP server normally fixes this problem. The external server will deliver mail from all sorts of domains, because you already authenticated yourself to use it. It won't have a problem with the "From:" email address.
That does not explain why it quit working all of the sudden. It's possible the web host tweaked their security settings or upgraded software somewhere. The important thing is that you got it working again.
Posted 9 years ago on Tuesday March 19, 2013 | Permalink