Note to indicate that the 'From' field being populated may cause messages to be filtered s SPAM

We have discovered that when sending a Scheduled Report to a recipient at Gmail and some other email providers, and using PDF as the report type, the message is filtered as SPAM or Junk, or may be blocked by the provider completely. This occurs only when the "From" field on the form contains a value. The solution is to leave the field blank. The request is for some indication of this in the form itself or a pop-up info for this.