Latest Version 2.6.1 Email Notification not working

After updating to latest version (2.61.) We are facing following error while sending email notifications.

“WordPress was unable to send the notification email. Cannot send email because the TO address is invalid.”

Debugged a bit an found in common.php file on line number 1873 under function send_notification()

following code is not working properly:
$notification = gf_apply_filters( array( ‘gform_notification’, $form[‘id’] ), $notification, $form, $lead );

is returning empty $notification object. If I comment it then email notifications start working.

Hey there,

From what you’ve explained, it sounds like there may be a plugin or theme conflict causing the issue. Follow this debugging guide and see if it helps you track down the cause: Testing for a Theme/Plugin Conflict using the Health Check & Troubleshooting Plugin - Gravity Forms Documentation

I have the same issue. Notifications are not sending nor is anything being logged when I try to send them.
I deactivated ALL of my plug-ins (most of which are Gravity Forms add-ons) except WP Mail SMTP and WP HTML Mail then tried again and it appears to have sent.

As an aside it is consistently frustrating to hear that basic Gravity forms functions do not work as expected unless you purchase an add-on. The add-ons are then frought with their own conflict issues and bugs.
I can honestly say at this point (5 months in) I regret spending the money and time on trying to use Gravity Forms and wish I had just stayed with google forms and my spreadsheets. The amount of time I have wasted troubleshooting website issues is significantly more than what I would have spent directly communicating with customers.

For notification issues, you can start with these troubleshooting steps:

Notification issues are very common and we’re happy to help if you open a support ticket:
https://www.gravityforms.com/open-support-ticket/technical/

Thank you. I have read this article MULTIPLE times over the past three days and have definitely been troubleshooting. The notes were not passed onto the GF entry which indicates an issue at the Gravity Forms level.
Unfortunately I do not have the time to endlessly troubleshoot these forms and why they don’t work. Which is what I seem to constantly have to do.

In that case Krystal, I recommend opening a support ticket. If you enable logging and test the form, then include the system report with your support ticket, we should be able to quickly help you find the issue.

https://www.gravityforms.com/open-support-ticket/technical/

Thank you