This error message is shown if your customers try to edit data through a landing page and the internal sender is not configured correctly.

If you want to receive an email when one of your customers edit some data, then you can configure this here on the landing page itself:
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Here is where you can configure from what email address the notice should be sent:
​Configure landing page email
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This email should already have been set up to send out from webCRM before it will work. Your customers will not be able to see this email address.
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​Here is how you set up the integration with Exchange/Office 365 email
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